FA-87786 / Collision detection broadphase / Open access

Insertion sort ignores endpoint kind on equal coordinates · case 01

Boxes that move into touching contact never begin a pair.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The swap test compares coordinates only.

VERIFIED REPAIR

Order by (x, min-before-max).

Unsuccessful approach: Ordering max before min on ties treats touching as separated.

Case contract

solve(prev, curr): incremental sweep-and-prune on x. Endpoints [x, 0=min/1=max, id] of prev are sorted, refreshed with curr coordinates and insertion-sorted by (x, kind). Each swap where a min passes left over a max begins a pair (if y overlaps in curr); a max passing left over a min ends a pair. Return [sorted begin pairs, sorted end pairs, swap count], pairs as [min,max].

Why this case matters

Broadphase stages decide which object pairs ever reach narrowphase; a wrong boundary, ordering or bookkeeping rule silently drops real contacts or floods the solver with false candidates.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(prev, curr):
    old = {b[0]: b for b in prev}
    new = {b[0]: b for b in curr}
    E = []
    for i, b in old.items():
        E.append([b[1], 0, i])
        E.append([b[3], 1, i])
    E.sort()
    for e in E:
        b = new[e[2]]
        e[0] = b[1] if e[1] == 0 else b[3]
    def yover(a, c):
        return new[a][2] <= new[c][4] and new[c][2] <= new[a][4]
    begins, ends = set(), set()
    swaps = 0
    for i in range(1, len(E)):
        j = i
        while j > 0 and E[j - 1][0] > E[j][0]:
            e, f = E[j], E[j - 1]
            E[j - 1], E[j] = e, f
            swaps += 1
            p = (min(e[2], f[2]), max(e[2], f[2]))
            if e[1] == 0 and f[1] == 1:
                if yover(e[2], f[2]):
                    begins.add(p)
            elif e[1] == 1 and f[1] == 0:
                ends.add(p)
            j -= 1
    return [sorted(list(p) for p in begins), sorted(list(p) for p in ends), swaps]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[[[38, -5.0, 2.0, -4.0, 4.0], [19, -4.0, 5.0, -4.0, 5.0], [27, -2.0, -5.0, -2.0, -3.0], [21, -2.0, -2.0, 1.0, 0.0], [12, 2.0, -5.0, 5.0, -3.0]], [[38, -1.0, 3.0, 0.0, 5.0], [19, -5.0, 5.0, -5.0, 5.0], [27, -5.0, -4.0, -5.0, -2.0], [21, 2.0, -3.0, 5.0, -1.0], [12, 6.0, -4.0, 9.0, -2.0]]], [[], [[19, 38], [21, 27], [27, 38]], 9]], [[[[22, 2.0, 1.0, 3.0, 1.0], [28, 3.0, 0.0, 4.0, 0.0], [21, -2.0, -2.0, 1.0, -1.0], [33, -1.0, 1.0, 0.0, 2.0], [11, 2.0, 5.0, 5.0, 5.0], [18, -1.0, 1.0, -1.0, 1.0]], [[22, 6.0, 1.0, 7.0, 1.0], [28, 5.0, 0.0, 6.0, 0.0], [21, 0.0, -3.0, 3.0, -2.0], [33, -4.0, 1.0, -3.0, 2.0], [11, 6.0, 5.0, 9.0, 5.0], [18, 0.0, 2.0, 0.0, 2.0]]], [[], [[18, 33], [21, 33]], 8]], [[[[36, 4.0, -3.0, 4.0, -2.0], [30, 5.0, 1.0, 5.0, 1.0]], [[36, 4.0, -3.0, 4.0, -2.0], [30, 5.0, 1.0, 5.0, 1.0]]], [[], [], 0]], [[[[3, 3.0, 0.0, 4.0, 3.0], [1, 4.0, -1.0, 6.0, 1.0]], [[3, 0.0, 1.0, 1.0, 4.0], [1, 1.0, -1.0, 3.0, 1.0]]], [[], [], 0]], [[[[5, -4.0, -1.0, -2.0, 0.0], [15, 2.0, -2.0, 5.0, -2.0]], [[5, -4.0, -1.0, -2.0, 0.0], [15, 1.0, -3.0, 4.0, -3.0]]], [[], [], 0]], [[[[20, 1.0, -3.0, 4.0, -3.0], [8, -4.0, -2.0, -2.0, 1.0], [29, 1.0, 2.0, 4.0, 4.0], [36, 0.0, 4.0, 2.0, 7.0]], [[20, 1.0, -2.0, 4.0, -2.0], [8, -2.0, -1.0, 0.0, 2.0], [29, 5.0, 2.0, 8.0, 4.0], [36, 0.0, 5.0, 2.0, 8.0]]], [[], [[20, 29], [29, 36]], 3]], [[[[32, -2.0, -1.0, -2.0, 2.0], [33, 1.0, -4.0, 2.0, -2.0], [12, 3.0, 1.0, 5.0, 2.0], [5, 1.0, 5.0, 3.0, 7.0]], [[32, -1.0, -1.0, -1.0, 2.0], [33, 1.0, -5.0, 2.0, -3.0], [12, 7.0, 1.0, 9.0, 2.0], [5, -2.0, 6.0, 0.0, 8.0]]], [[], [[5, 12], [5, 33]], 5]], [[[[21, -2.0, -5.0, 1.0, -5.0], [19, 3.0, -5.0, 5.0, -4.0], [36, -2.0, -1.0, 0.0, 0.0], [16, 5.0, -1.0, 5.0, 0.0], [1, -3.0, 3.0, -3.0, 4.0]], [[21, -1.0, -5.0, 2.0, -5.0], [19, 2.0, -6.0, 4.0, -5.0], [36, -2.0, 0.0, 0.0, 1.0], [16, 9.0, -1.0, 9.0, 0.0], [1, -3.0, 3.0, -3.0, 4.0]]], [[[19, 21]], [[16, 19]], 4]]], [[[[[6, 5.0, 4.0, 5.0, 7.0], [38, -3.0, 0.0, 0.0, 3.0], [18, -5.0, -3.0, -4.0, -2.0], [9, -5.0, 5.0, -5.0, 7.0], [27, 0.0, 4.0, 1.0, 6.0]], [[6, 7.0, 4.0, 7.0, 7.0], [38, -3.0, 0.0, 0.0, 3.0], [18, -4.0, -3.0, -3.0, -2.0], [9, -5.0, 5.0, -5.0, 7.0], [27, -1.0, 4.0, 0.0, 6.0]]], [[], [[9, 18]], 2]], [[[[31, 1.0, 0.0, 1.0, 0.0], [38, -4.0, 1.0, -2.0, 4.0], [5, -1.0, -1.0, 0.0, -1.0], [39, 2.0, -3.0, 5.0, -3.0], [27, 3.0, 2.0, 3.0, 5.0], [4, -4.0, -1.0, -3.0, 2.0]], [[31, 1.0, 1.0, 1.0, 1.0], [38, -2.0, 1.0, 0.0, 4.0], [5, 1.0, -1.0, 2.0, -1.0], [39, 6.0, -3.0, 9.0, -3.0], [27, 0.0, 1.0, 0.0, 4.0], [4, -4.0, -1.0, -3.0, 2.0]]], [[[27, 31], [27, 38]], [[4, 38], [5, 27], [27, 31], [27, 39]], 14]], [[[[37, -1.0, -5.0, 1.0, -3.0], [39, -3.0, 0.0, -2.0, 2.0], [12, 1.0, -5.0, 4.0, -3.0], [1, -4.0, -4.0, -2.0, -2.0], [16, 1.0, -3.0, 2.0, 0.0]], [[37, 0.0, -4.0, 2.0, -2.0], [39, -3.0, -1.0, -2.0, 1.0], [12, -2.0, -4.0, 1.0, -2.0], [1, -3.0, -3.0, -1.0, -1.0], [16, 0.0, -2.0, 1.0, 1.0]]], [[[1, 12]], [], 6]], [[[[34, -5.0, 5.0, -3.0, 6.0], [25, 3.0, -4.0, 6.0, -1.0], [10, -5.0, -3.0, -4.0, -2.0], [2, -4.0, 0.0, -2.0, 0.0], [13, -3.0, 5.0, -3.0, 6.0], [3, -1.0, 2.0, 0.0, 2.0], [20, 1.0, -4.0, 1.0, -3.0]], [[34, -6.0, 4.0, -4.0, 5.0], [25, 3.0, -4.0, 6.0, -1.0], [10, -5.0, -2.0, -4.0, -1.0], [2, -3.0, -1.0, -1.0, -1.0], [13, -1.0, 4.0, -1.0, 5.0], [3, 3.0, 2.0, 4.0, 2.0], [20, 0.0, -4.0, 0.0, -3.0]]], [[], [[2, 10], [2, 34], [3, 20], [13, 34]], 10]], [[[[10, 0.0, -5.0, 1.0, -5.0], [12, -3.0, -3.0, 0.0, -2.0]], [[10, 1.0, -5.0, 2.0, -5.0], [12, -2.0, -2.0, 1.0, -1.0]]], [[], [], 0]], [[[[13, -2.0, 1.0, -1.0, 2.0], [20, -5.0, 0.0, -4.0, 1.0], [37, 0.0, 5.0, 3.0, 8.0], [8, 5.0, -3.0, 5.0, -2.0], [2, 3.0, -1.0, 6.0, 0.0]], [[13, -3.0, 1.0, -2.0, 2.0], [20, -6.0, -1.0, -5.0, 0.0], [37, 4.0, 6.0, 7.0, 9.0], [8, 5.0, -2.0, 5.0, -1.0], [2, 2.0, -1.0, 5.0, 0.0]]], [[], [], 4]], [[[[24, -1.0, -2.0, 2.0, 1.0], [30, 0.0, -3.0, 3.0, -2.0], [37, -5.0, 1.0, -5.0, 4.0], [18, 1.0, 2.0, 2.0, 4.0], [26, -3.0, -4.0, -2.0, -3.0], [29, 3.0, 2.0, 5.0, 4.0]], [[24, -2.0, -3.0, 1.0, 0.0], [30, 0.0, -2.0, 3.0, -1.0], [37, -4.0, 0.0, -4.0, 3.0], [18, 5.0, 3.0, 6.0, 5.0], [26, -3.0, -4.0, -2.0, -3.0], [29, 3.0, 2.0, 5.0, 4.0]]], [[[18, 29], [24, 26]], [[18, 24], [18, 30]], 8]], [[[[25, -3.0, 5.0, -1.0, 8.0], [9, -1.0, -4.0, 0.0, -3.0], [21, 0.0, -1.0, 3.0, 0.0], [3, 0.0, 3.0, 0.0, 5.0], [4, 4.0, -2.0, 6.0, -2.0]], [[25, -3.0, 4.0, -1.0, 7.0], [9, 1.0, -4.0, 2.0, -3.0], [21, 2.0, -2.0, 5.0, -1.0], [3, 0.0, 4.0, 0.0, 6.0], [4, 4.0, -2.0, 6.0, -2.0]]], [[[4, 21]], [[3, 9], [3, 21], [9, 25]], 5]]], [[[[[3, 5.0, 4.0, 6.0, 7.0], [21, 4.0, 2.0, 6.0, 2.0], [35, 4.0, -3.0, 6.0, 0.0], [14, -4.0, -5.0, -4.0, -5.0], [31, -2.0, 2.0, -1.0, 2.0], [20, 5.0, 3.0, 8.0, 5.0], [34, 1.0, 5.0, 2.0, 6.0]], [[3, 4.0, 4.0, 5.0, 7.0], [21, 5.0, 2.0, 7.0, 2.0], [35, 5.0, -3.0, 7.0, 0.0], [14, -2.0, -5.0, -2.0, -5.0], [31, -2.0, 3.0, -1.0, 3.0], [20, 5.0, 2.0, 8.0, 4.0], [34, 1.0, 6.0, 2.0, 7.0]]], [[], [], 3]], [[[[25, -4.0, 3.0, -4.0, 5.0], [8, -1.0, 1.0, 2.0, 2.0], [15, -3.0, 4.0, 0.0, 4.0]], [[25, -3.0, 2.0, -3.0, 4.0], [8, -2.0, 1.0, 1.0, 2.0], [15, 1.0, 5.0, 4.0, 5.0]]], [[], [], 2]], [[[[3, -5.0, -3.0, -3.0, 0.0], [10, 1.0, 3.0, 3.0, 4.0], [38, -5.0, 5.0, -4.0, 6.0]], [[3, -8.0, -2.0, -6.0, 1.0], [10, -2.0, 4.0, 0.0, 5.0], [38, -4.0, 5.0, -3.0, 6.0]]], [[], [[3, 38]], 2]], [[[[20, -5.0, -1.0, -5.0, 2.0], [7, 3.0, 0.0, 5.0, 1.0]], [[20, -5.0, -1.0, -5.0, 2.0], [7, 7.0, 0.0, 9.0, 1.0]]], [[], [], 0]], [[[[11, -2.0, -1.0, -2.0, 0.0], [14, 1.0, -4.0, 2.0, -3.0], [32, 5.0, 3.0, 6.0, 4.0], [6, -2.0, 5.0, 1.0, 8.0], [39, 0.0, -4.0, 1.0, -3.0], [8, -1.0, -3.0, 2.0, 0.0]], [[11, -5.0, 0.0, -5.0, 1.0], [14, 2.0, -5.0, 3.0, -4.0], [32, 5.0, 2.0, 6.0, 3.0], [6, 2.0, 4.0, 5.0, 7.0], [39, 0.0, -4.0, 1.0, -3.0], [8, 0.0, -3.0, 3.0, 0.0]]], [[], [[6, 11], [6, 39], [14, 39]], 10]], [[[[38, -3.0, -5.0, -3.0, -4.0], [10, 4.0, 1.0, 6.0, 3.0], [15, 1.0, 0.0, 3.0, 3.0], [23, -4.0, -2.0, -1.0, 0.0], [24, -1.0, 3.0, 2.0, 4.0], [14, 3.0, -4.0, 5.0, -3.0], [26, -2.0, 3.0, 1.0, 5.0], [20, -5.0, 4.0, -4.0, 5.0]], [[38, -6.0, -6.0, -6.0, -5.0], [10, 1.0, 0.0, 3.0, 2.0], [15, 1.0, 1.0, 3.0, 4.0], [23, 0.0, -2.0, 3.0, 0.0], [24, 0.0, 2.0, 3.0, 3.0], [14, 5.0, -5.0, 7.0, -4.0], [26, -2.0, 2.0, 1.0, 4.0], [20, -3.0, 5.0, -2.0, 6.0]]], [[[10, 15], [10, 23], [10, 24], [10, 26]], [[10, 14], [14, 15], [20, 23], [20, 38], [23, 38]], 19]], [[[[3, 1.0, -5.0, 2.0, -5.0], [32, 2.0, -5.0, 3.0, -3.0], [38, -3.0, 5.0, -1.0, 5.0], [1, 2.0, 3.0, 4.0, 3.0], [13, -3.0, -4.0, 0.0, -3.0]], [[3, 2.0, -4.0, 3.0, -4.0], [32, 2.0, -5.0, 3.0, -3.0], [38, -3.0, 5.0, -1.0, 5.0], [1, 3.0, 2.0, 5.0, 2.0], [13, -3.0, -5.0, 0.0, -4.0]]], [[], [], 1]], [[[[7, -2.0, -1.0, 0.0, 0.0], [10, -5.0, 1.0, -5.0, 2.0], [13, -4.0, 0.0, -1.0, 2.0], [33, 5.0, -1.0, 6.0, 0.0], [31, -4.0, -1.0, -1.0, 0.0]], [[7, -1.0, -1.0, 1.0, 0.0], [10, -3.0, 1.0, -3.0, 2.0], [13, -4.0, -1.0, -1.0, 1.0], [33, 5.0, -1.0, 6.0, 0.0], [31, -4.0, -2.0, -1.0, -1.0]]], [[[10, 13]], [], 4]]], [[[[[18, -3.0, 3.0, -1.0, 4.0], [34, 1.0, -4.0, 1.0, -2.0], [23, 4.0, -2.0, 7.0, 1.0]], [[18, -3.0, 3.0, -1.0, 4.0], [34, 3.0, -4.0, 3.0, -2.0], [23, 3.0, -2.0, 6.0, 1.0]]], [[[23, 34]], [], 1]], [[[[30, 5.0, 4.0, 7.0, 7.0], [13, -5.0, 1.0, -5.0, 2.0], [35, -3.0, 0.0, -1.0, 0.0], [14, -5.0, 3.0, -5.0, 5.0]], [[30, 2.0, 5.0, 4.0, 8.0], [13, -4.0, 0.0, -4.0, 1.0], [35, -2.0, 0.0, 0.0, 0.0], [14, -5.0, 3.0, -5.0, 5.0]]], [[], [[13, 14]], 3]], [[[[8, -1.0, -1.0, -1.0, -1.0], [9, 4.0, 0.0, 4.0, 3.0], [30, -3.0, 5.0, -1.0, 5.0], [32, 0.0, 2.0, 1.0, 5.0], [3, -3.0, 1.0, 0.0, 1.0], [18, -2.0, 4.0, -2.0, 7.0], [23, 5.0, 2.0, 5.0, 2.0], [39, -4.0, 4.0, -1.0, 5.0]], [[8, 0.0, -1.0, 0.0, -1.0], [9, 1.0, -1.0, 1.0, 2.0], [30, -6.0, 4.0, -4.0, 4.0], [32, -1.0, 1.0, 0.0, 4.0], [3, -3.0, 2.0, 0.0, 2.0], [18, -3.0, 4.0, -3.0, 7.0], [23, 5.0, 1.0, 5.0, 1.0], [39, -4.0, 3.0, -1.0, 4.0]]], [[[32, 39]], [[3, 30], [8, 30], [8, 39], [18, 30]], 12]], [[[[15, -4.0, 5.0, -1.0, 6.0], [21, -2.0, 1.0, -1.0, 2.0], [16, 5.0, 2.0, 8.0, 3.0], [39, 1.0, 1.0, 4.0, 1.0], [27, 1.0, -3.0, 1.0, -2.0], [12, 5.0, -5.0, 8.0, -5.0]], [[15, -4.0, 4.0, -1.0, 5.0], [21, -1.0, 1.0, 0.0, 2.0], [16, 6.0, 2.0, 9.0, 3.0], [39, 3.0, 1.0, 6.0, 1.0], [27, 3.0, -3.0, 3.0, -2.0], [12, 5.0, -5.0, 8.0, -5.0]]], [[], [], 2]], [[[[33, -3.0, 1.0, -1.0, 2.0], [4, 1.0, -5.0, 4.0, -4.0], [36, -4.0, 2.0, -3.0, 5.0]], [[33, -2.0, 2.0, 0.0, 3.0], [4, -2.0, -5.0, 1.0, -4.0], [36, -2.0, 1.0, -1.0, 4.0]]], [[], [], 2]], [[[[12, 2.0, -4.0, 5.0, -1.0], [4, 5.0, 0.0, 6.0, 0.0], [19, -5.0, -2.0, -4.0, -1.0], [16, -1.0, -3.0, 0.0, 0.0], [22, 5.0, 2.0, 5.0, 3.0]], [[12, 3.0, -5.0, 6.0, -2.0], [4, 5.0, 0.0, 6.0, 0.0], [19, -3.0, -2.0, -2.0, -1.0], [16, -4.0, -2.0, -3.0, 1.0], [22, 9.0, 3.0, 9.0, 4.0]]], [[[16, 19]], [[4, 22], [12, 22]], 6]], [[[[21, -1.0, 3.0, -1.0, 3.0], [13, -2.0, 1.0, 1.0, 1.0], [33, 4.0, -2.0, 7.0, 0.0], [39, 1.0, -3.0, 2.0, -3.0]], [[21, 0.0, 3.0, 0.0, 3.0], [13, -2.0, 2.0, 1.0, 2.0], [33, 6.0, -3.0, 9.0, -1.0], [39, 2.0, -4.0, 3.0, -4.0]]], [[], [[13, 39]], 1]], [[[[8, 5.0, 2.0, 6.0, 2.0], [5, -3.0, -5.0, -1.0, -4.0], [27, 0.0, 1.0, 1.0, 1.0], [16, 4.0, 2.0, 6.0, 3.0], [38, 5.0, -4.0, 8.0, -2.0], [19, -5.0, 2.0, -5.0, 5.0], [20, 1.0, 1.0, 3.0, 1.0], [31, 5.0, -1.0, 8.0, 2.0], [22, -2.0, -4.0, -2.0, -2.0]], [[8, 5.0, 3.0, 6.0, 3.0], [5, -3.0, -5.0, -1.0, -4.0], [27, 2.0, 2.0, 3.0, 2.0], [16, 1.0, 2.0, 3.0, 3.0], [38, 7.0, -3.0, 10.0, -1.0], [19, -5.0, 3.0, -5.0, 6.0], [20, 2.0, 1.0, 4.0, 1.0], [31, 9.0, 0.0, 12.0, 3.0], [22, 0.0, -3.0, 0.0, -1.0]]], [[[16, 27]], [[5, 22], [8, 16], [8, 31], [8, 38], [16, 31], [16, 38]], 15]]], [[[[[24, -3.0, 5.0, -1.0, 5.0], [29, -4.0, -1.0, -2.0, 0.0], [15, -4.0, -4.0, -4.0, -3.0], [6, 1.0, -2.0, 2.0, 1.0], [11, 4.0, 5.0, 7.0, 6.0], [13, 1.0, 5.0, 4.0, 5.0], [14, 1.0, -5.0, 4.0, -4.0], [19, 5.0, 5.0, 7.0, 6.0], [16, 5.0, 4.0, 5.0, 4.0]], [[24, -3.0, 5.0, -1.0, 5.0], [29, -5.0, -1.0, -3.0, 0.0], [15, 0.0, -4.0, 0.0, -3.0], [6, 1.0, -3.0, 2.0, 0.0], [11, 4.0, 6.0, 7.0, 7.0], [13, 2.0, 5.0, 5.0, 5.0], [14, 5.0, -5.0, 8.0, -4.0], [19, 5.0, 4.0, 7.0, 5.0], [16, 5.0, 4.0, 5.0, 4.0]]], [[[13, 19]], [[6, 14], [15, 24], [15, 29]], 16]], [[[[23, 3.0, 0.0, 6.0, 0.0], [25, -3.0, -1.0, 0.0, 2.0], [7, -3.0, 1.0, 0.0, 1.0], [21, -5.0, 4.0, -2.0, 6.0], [37, 5.0, 1.0, 5.0, 3.0], [30, -3.0, -1.0, -2.0, 1.0], [26, -3.0, 3.0, 0.0, 5.0], [5, -5.0, 3.0, -3.0, 5.0]], [[23, 2.0, -1.0, 5.0, -1.0], [25, -3.0, -1.0, 0.0, 2.0], [7, -6.0, 2.0, -3.0, 2.0], [21, -5.0, 4.0, -2.0, 6.0], [37, 5.0, 1.0, 5.0, 3.0], [30, -4.0, -1.0, -3.0, 1.0], [26, -2.0, 2.0, 1.0, 4.0], [5, -5.0, 2.0, -3.0, 4.0]]], [[], [[5, 26], [7, 26], [26, 30]], 9]], [[[[33, -1.0, -1.0, 2.0, 1.0], [8, 2.0, -3.0, 4.0, -1.0], [26, 4.0, 3.0, 6.0, 6.0], [17, -5.0, 4.0, -4.0, 6.0]], [[33, -2.0, -1.0, 1.0, 1.0], [8, 4.0, -4.0, 6.0, -2.0], [26, 1.0, 3.0, 3.0, 6.0], [17, -6.0, 4.0, -5.0, 6.0]]], [[], [[8, 26], [8, 33]], 5]], [[[[28, 2.0, 2.0, 5.0, 2.0], [24, -3.0, 4.0, -3.0, 4.0], [29, -5.0, 4.0, -4.0, 5.0], [10, 1.0, 1.0, 4.0, 2.0], [33, -2.0, -4.0, -1.0, -3.0], [12, 2.0, 3.0, 2.0, 3.0], [39, -5.0, -3.0, -2.0, -2.0], [1, 3.0, -5.0, 4.0, -4.0]], [[28, 2.0, 2.0, 5.0, 2.0], [24, -4.0, 5.0, -4.0, 5.0], [29, -6.0, 3.0, -5.0, 4.0], [10, 3.0, 1.0, 6.0, 2.0], [33, -3.0, -4.0, -2.0, -3.0], [12, 4.0, 3.0, 4.0, 3.0], [39, -3.0, -2.0, 0.0, -1.0], [1, 2.0, -5.0, 3.0, -4.0]]], [[], [[1, 12], [24, 39], [29, 39]], 12]], [[[[23, 1.0, 0.0, 2.0, 1.0], [30, 5.0, -2.0, 5.0, -1.0], [16, 3.0, 5.0, 6.0, 8.0], [2, -3.0, 2.0, 0.0, 2.0]], [[23, 0.0, 0.0, 1.0, 1.0], [30, 7.0, -2.0, 7.0, -1.0], [16, 5.0, 4.0, 8.0, 7.0], [2, -6.0, 3.0, -3.0, 3.0]]], [[], [], 0]], [[[[28, 0.0, -4.0, 2.0, -4.0], [20, 2.0, -5.0, 2.0, -3.0]], [[28, 4.0, -3.0, 6.0, -3.0], [20, 2.0, -5.0, 2.0, -3.0]]], [[], [[20, 28]], 2]], [[[[10, -5.0, -1.0, -3.0, -1.0], [17, 3.0, 4.0, 6.0, 6.0], [30, 0.0, -1.0, 0.0, -1.0], [25, 2.0, -4.0, 3.0, -4.0], [39, -2.0, 3.0, -2.0, 6.0]], [[10, -5.0, -2.0, -3.0, -2.0], [17, 3.0, 4.0, 6.0, 6.0], [30, 0.0, -1.0, 0.0, -1.0], [25, 2.0, -4.0, 3.0, -4.0], [39, -3.0, 3.0, -3.0, 6.0]]], [[], [], 1]], [[[[7, 1.0, 5.0, 1.0, 8.0], [12, -1.0, -4.0, 1.0, -1.0], [4, -3.0, -4.0, -2.0, -3.0], [26, 4.0, 5.0, 4.0, 5.0], [19, -4.0, -2.0, -4.0, 0.0], [6, 5.0, 3.0, 7.0, 3.0], [5, -1.0, 2.0, -1.0, 4.0], [30, 4.0, 0.0, 5.0, 0.0]], [[7, 1.0, 5.0, 1.0, 8.0], [12, -1.0, -4.0, 1.0, -1.0], [4, -3.0, -5.0, -2.0, -4.0], [26, 4.0, 5.0, 4.0, 5.0], [19, -4.0, -3.0, -4.0, -1.0], [6, 9.0, 2.0, 11.0, 2.0], [5, -2.0, 3.0, -2.0, 5.0], [30, 5.0, 1.0, 6.0, 1.0]]], [[], [[5, 12], [6, 30], [26, 30]], 4]]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("case %d" % i, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
case 0	`[[], [[19, 38], [21, 27], [27, 38]], 8]`	`[[], [[19, 38], [21, 27], [27, 38]], 9]`	Failed
case 1	`[[], [[18, 33], [21, 33]], 8]`	`[[], [[18, 33], [21, 33]], 8]`	Passed
case 2	`[[], [], 0]`	`[[], [], 0]`	Passed
case 3	`[[], [], 0]`	`[[], [], 0]`	Passed
case 4	`[[], [], 0]`	`[[], [], 0]`	Passed
case 5	`[[], [[20, 29], [29, 36]], 2]`	`[[], [[20, 29], [29, 36]], 3]`	Failed
case 6	`[[], [[5, 12], [5, 33]], 5]`	`[[], [[5, 12], [5, 33]], 5]`	Passed
case 7	`[[], [[16, 19]], 3]`	`[[[19, 21]], [[16, 19]], 4]`	Failed

SHA-256 / d1252260672f7bf0f2d2c5b05e136e778c67d0884bd93767cf8c864a589e2b84

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(prev, curr):
    old = {b[0]: b for b in prev}
    new = {b[0]: b for b in curr}
    E = []
    for i, b in old.items():
        E.append([b[1], 0, i])
        E.append([b[3], 1, i])
    E.sort()
    for e in E:
        b = new[e[2]]
        e[0] = b[1] if e[1] == 0 else b[3]
    def yover(a, c):
        return new[a][2] <= new[c][4] and new[c][2] <= new[a][4]
    begins, ends = set(), set()
    swaps = 0
    for i in range(1, len(E)):
        j = i
        while j > 0 and (E[j - 1][0], -E[j - 1][1]) > (E[j][0], -E[j][1]):
            e, f = E[j], E[j - 1]
            E[j - 1], E[j] = e, f
            swaps += 1
            p = (min(e[2], f[2]), max(e[2], f[2]))
            if e[1] == 0 and f[1] == 1:
                if yover(e[2], f[2]):
                    begins.add(p)
            elif e[1] == 1 and f[1] == 0:
                ends.add(p)
            j -= 1
    return [sorted(list(p) for p in begins), sorted(list(p) for p in ends), swaps]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[[[38, -5.0, 2.0, -4.0, 4.0], [19, -4.0, 5.0, -4.0, 5.0], [27, -2.0, -5.0, -2.0, -3.0], [21, -2.0, -2.0, 1.0, 0.0], [12, 2.0, -5.0, 5.0, -3.0]], [[38, -1.0, 3.0, 0.0, 5.0], [19, -5.0, 5.0, -5.0, 5.0], [27, -5.0, -4.0, -5.0, -2.0], [21, 2.0, -3.0, 5.0, -1.0], [12, 6.0, -4.0, 9.0, -2.0]]], [[], [[19, 38], [21, 27], [27, 38]], 9]], [[[[22, 2.0, 1.0, 3.0, 1.0], [28, 3.0, 0.0, 4.0, 0.0], [21, -2.0, -2.0, 1.0, -1.0], [33, -1.0, 1.0, 0.0, 2.0], [11, 2.0, 5.0, 5.0, 5.0], [18, -1.0, 1.0, -1.0, 1.0]], [[22, 6.0, 1.0, 7.0, 1.0], [28, 5.0, 0.0, 6.0, 0.0], [21, 0.0, -3.0, 3.0, -2.0], [33, -4.0, 1.0, -3.0, 2.0], [11, 6.0, 5.0, 9.0, 5.0], [18, 0.0, 2.0, 0.0, 2.0]]], [[], [[18, 33], [21, 33]], 8]], [[[[36, 4.0, -3.0, 4.0, -2.0], [30, 5.0, 1.0, 5.0, 1.0]], [[36, 4.0, -3.0, 4.0, -2.0], [30, 5.0, 1.0, 5.0, 1.0]]], [[], [], 0]], [[[[3, 3.0, 0.0, 4.0, 3.0], [1, 4.0, -1.0, 6.0, 1.0]], [[3, 0.0, 1.0, 1.0, 4.0], [1, 1.0, -1.0, 3.0, 1.0]]], [[], [], 0]], [[[[5, -4.0, -1.0, -2.0, 0.0], [15, 2.0, -2.0, 5.0, -2.0]], [[5, -4.0, -1.0, -2.0, 0.0], [15, 1.0, -3.0, 4.0, -3.0]]], [[], [], 0]], [[[[20, 1.0, -3.0, 4.0, -3.0], [8, -4.0, -2.0, -2.0, 1.0], [29, 1.0, 2.0, 4.0, 4.0], [36, 0.0, 4.0, 2.0, 7.0]], [[20, 1.0, -2.0, 4.0, -2.0], [8, -2.0, -1.0, 0.0, 2.0], [29, 5.0, 2.0, 8.0, 4.0], [36, 0.0, 5.0, 2.0, 8.0]]], [[], [[20, 29], [29, 36]], 3]], [[[[32, -2.0, -1.0, -2.0, 2.0], [33, 1.0, -4.0, 2.0, -2.0], [12, 3.0, 1.0, 5.0, 2.0], [5, 1.0, 5.0, 3.0, 7.0]], [[32, -1.0, -1.0, -1.0, 2.0], [33, 1.0, -5.0, 2.0, -3.0], [12, 7.0, 1.0, 9.0, 2.0], [5, -2.0, 6.0, 0.0, 8.0]]], [[], [[5, 12], [5, 33]], 5]], [[[[21, -2.0, -5.0, 1.0, -5.0], [19, 3.0, -5.0, 5.0, -4.0], [36, -2.0, -1.0, 0.0, 0.0], [16, 5.0, -1.0, 5.0, 0.0], [1, -3.0, 3.0, -3.0, 4.0]], [[21, -1.0, -5.0, 2.0, -5.0], [19, 2.0, -6.0, 4.0, -5.0], [36, -2.0, 0.0, 0.0, 1.0], [16, 9.0, -1.0, 9.0, 0.0], [1, -3.0, 3.0, -3.0, 4.0]]], [[[19, 21]], [[16, 19]], 4]]], [[[[[6, 5.0, 4.0, 5.0, 7.0], [38, -3.0, 0.0, 0.0, 3.0], [18, -5.0, -3.0, -4.0, -2.0], [9, -5.0, 5.0, -5.0, 7.0], [27, 0.0, 4.0, 1.0, 6.0]], [[6, 7.0, 4.0, 7.0, 7.0], [38, -3.0, 0.0, 0.0, 3.0], [18, -4.0, -3.0, -3.0, -2.0], [9, -5.0, 5.0, -5.0, 7.0], [27, -1.0, 4.0, 0.0, 6.0]]], [[], [[9, 18]], 2]], [[[[31, 1.0, 0.0, 1.0, 0.0], [38, -4.0, 1.0, -2.0, 4.0], [5, -1.0, -1.0, 0.0, -1.0], [39, 2.0, -3.0, 5.0, -3.0], [27, 3.0, 2.0, 3.0, 5.0], [4, -4.0, -1.0, -3.0, 2.0]], [[31, 1.0, 1.0, 1.0, 1.0], [38, -2.0, 1.0, 0.0, 4.0], [5, 1.0, -1.0, 2.0, -1.0], [39, 6.0, -3.0, 9.0, -3.0], [27, 0.0, 1.0, 0.0, 4.0], [4, -4.0, -1.0, -3.0, 2.0]]], [[[27, 31], [27, 38]], [[4, 38], [5, 27], [27, 31], [27, 39]], 14]], [[[[37, -1.0, -5.0, 1.0, -3.0], [39, -3.0, 0.0, -2.0, 2.0], [12, 1.0, -5.0, 4.0, -3.0], [1, -4.0, -4.0, -2.0, -2.0], [16, 1.0, -3.0, 2.0, 0.0]], [[37, 0.0, -4.0, 2.0, -2.0], [39, -3.0, -1.0, -2.0, 1.0], [12, -2.0, -4.0, 1.0, -2.0], [1, -3.0, -3.0, -1.0, -1.0], [16, 0.0, -2.0, 1.0, 1.0]]], [[[1, 12]], [], 6]], [[[[34, -5.0, 5.0, -3.0, 6.0], [25, 3.0, -4.0, 6.0, -1.0], [10, -5.0, -3.0, -4.0, -2.0], [2, -4.0, 0.0, -2.0, 0.0], [13, -3.0, 5.0, -3.0, 6.0], [3, -1.0, 2.0, 0.0, 2.0], [20, 1.0, -4.0, 1.0, -3.0]], [[34, -6.0, 4.0, -4.0, 5.0], [25, 3.0, -4.0, 6.0, -1.0], [10, -5.0, -2.0, -4.0, -1.0], [2, -3.0, -1.0, -1.0, -1.0], [13, -1.0, 4.0, -1.0, 5.0], [3, 3.0, 2.0, 4.0, 2.0], [20, 0.0, -4.0, 0.0, -3.0]]], [[], [[2, 10], [2, 34], [3, 20], [13, 34]], 10]], [[[[10, 0.0, -5.0, 1.0, -5.0], [12, -3.0, -3.0, 0.0, -2.0]], [[10, 1.0, -5.0, 2.0, -5.0], [12, -2.0, -2.0, 1.0, -1.0]]], [[], [], 0]], [[[[13, -2.0, 1.0, -1.0, 2.0], [20, -5.0, 0.0, -4.0, 1.0], [37, 0.0, 5.0, 3.0, 8.0], [8, 5.0, -3.0, 5.0, -2.0], [2, 3.0, -1.0, 6.0, 0.0]], [[13, -3.0, 1.0, -2.0, 2.0], [20, -6.0, -1.0, -5.0, 0.0], [37, 4.0, 6.0, 7.0, 9.0], [8, 5.0, -2.0, 5.0, -1.0], [2, 2.0, -1.0, 5.0, 0.0]]], [[], [], 4]], [[[[24, -1.0, -2.0, 2.0, 1.0], [30, 0.0, -3.0, 3.0, -2.0], [37, -5.0, 1.0, -5.0, 4.0], [18, 1.0, 2.0, 2.0, 4.0], [26, -3.0, -4.0, -2.0, -3.0], [29, 3.0, 2.0, 5.0, 4.0]], [[24, -2.0, -3.0, 1.0, 0.0], [30, 0.0, -2.0, 3.0, -1.0], [37, -4.0, 0.0, -4.0, 3.0], [18, 5.0, 3.0, 6.0, 5.0], [26, -3.0, -4.0, -2.0, -3.0], [29, 3.0, 2.0, 5.0, 4.0]]], [[[18, 29], [24, 26]], [[18, 24], [18, 30]], 8]], [[[[25, -3.0, 5.0, -1.0, 8.0], [9, -1.0, -4.0, 0.0, -3.0], [21, 0.0, -1.0, 3.0, 0.0], [3, 0.0, 3.0, 0.0, 5.0], [4, 4.0, -2.0, 6.0, -2.0]], [[25, -3.0, 4.0, -1.0, 7.0], [9, 1.0, -4.0, 2.0, -3.0], [21, 2.0, -2.0, 5.0, -1.0], [3, 0.0, 4.0, 0.0, 6.0], [4, 4.0, -2.0, 6.0, -2.0]]], [[[4, 21]], [[3, 9], [3, 21], [9, 25]], 5]]], [[[[[3, 5.0, 4.0, 6.0, 7.0], [21, 4.0, 2.0, 6.0, 2.0], [35, 4.0, -3.0, 6.0, 0.0], [14, -4.0, -5.0, -4.0, -5.0], [31, -2.0, 2.0, -1.0, 2.0], [20, 5.0, 3.0, 8.0, 5.0], [34, 1.0, 5.0, 2.0, 6.0]], [[3, 4.0, 4.0, 5.0, 7.0], [21, 5.0, 2.0, 7.0, 2.0], [35, 5.0, -3.0, 7.0, 0.0], [14, -2.0, -5.0, -2.0, -5.0], [31, -2.0, 3.0, -1.0, 3.0], [20, 5.0, 2.0, 8.0, 4.0], [34, 1.0, 6.0, 2.0, 7.0]]], [[], [], 3]], [[[[25, -4.0, 3.0, -4.0, 5.0], [8, -1.0, 1.0, 2.0, 2.0], [15, -3.0, 4.0, 0.0, 4.0]], [[25, -3.0, 2.0, -3.0, 4.0], [8, -2.0, 1.0, 1.0, 2.0], [15, 1.0, 5.0, 4.0, 5.0]]], [[], [], 2]], [[[[3, -5.0, -3.0, -3.0, 0.0], [10, 1.0, 3.0, 3.0, 4.0], [38, -5.0, 5.0, -4.0, 6.0]], [[3, -8.0, -2.0, -6.0, 1.0], [10, -2.0, 4.0, 0.0, 5.0], [38, -4.0, 5.0, -3.0, 6.0]]], [[], [[3, 38]], 2]], [[[[20, -5.0, -1.0, -5.0, 2.0], [7, 3.0, 0.0, 5.0, 1.0]], [[20, -5.0, -1.0, -5.0, 2.0], [7, 7.0, 0.0, 9.0, 1.0]]], [[], [], 0]], [[[[11, -2.0, -1.0, -2.0, 0.0], [14, 1.0, -4.0, 2.0, -3.0], [32, 5.0, 3.0, 6.0, 4.0], [6, -2.0, 5.0, 1.0, 8.0], [39, 0.0, -4.0, 1.0, -3.0], [8, -1.0, -3.0, 2.0, 0.0]], [[11, -5.0, 0.0, -5.0, 1.0], [14, 2.0, -5.0, 3.0, -4.0], [32, 5.0, 2.0, 6.0, 3.0], [6, 2.0, 4.0, 5.0, 7.0], [39, 0.0, -4.0, 1.0, -3.0], [8, 0.0, -3.0, 3.0, 0.0]]], [[], [[6, 11], [6, 39], [14, 39]], 10]], [[[[38, -3.0, -5.0, -3.0, -4.0], [10, 4.0, 1.0, 6.0, 3.0], [15, 1.0, 0.0, 3.0, 3.0], [23, -4.0, -2.0, -1.0, 0.0], [24, -1.0, 3.0, 2.0, 4.0], [14, 3.0, -4.0, 5.0, -3.0], [26, -2.0, 3.0, 1.0, 5.0], [20, -5.0, 4.0, -4.0, 5.0]], [[38, -6.0, -6.0, -6.0, -5.0], [10, 1.0, 0.0, 3.0, 2.0], [15, 1.0, 1.0, 3.0, 4.0], [23, 0.0, -2.0, 3.0, 0.0], [24, 0.0, 2.0, 3.0, 3.0], [14, 5.0, -5.0, 7.0, -4.0], [26, -2.0, 2.0, 1.0, 4.0], [20, -3.0, 5.0, -2.0, 6.0]]], [[[10, 15], [10, 23], [10, 24], [10, 26]], [[10, 14], [14, 15], [20, 23], [20, 38], [23, 38]], 19]], [[[[3, 1.0, -5.0, 2.0, -5.0], [32, 2.0, -5.0, 3.0, -3.0], [38, -3.0, 5.0, -1.0, 5.0], [1, 2.0, 3.0, 4.0, 3.0], [13, -3.0, -4.0, 0.0, -3.0]], [[3, 2.0, -4.0, 3.0, -4.0], [32, 2.0, -5.0, 3.0, -3.0], [38, -3.0, 5.0, -1.0, 5.0], [1, 3.0, 2.0, 5.0, 2.0], [13, -3.0, -5.0, 0.0, -4.0]]], [[], [], 1]], [[[[7, -2.0, -1.0, 0.0, 0.0], [10, -5.0, 1.0, -5.0, 2.0], [13, -4.0, 0.0, -1.0, 2.0], [33, 5.0, -1.0, 6.0, 0.0], [31, -4.0, -1.0, -1.0, 0.0]], [[7, -1.0, -1.0, 1.0, 0.0], [10, -3.0, 1.0, -3.0, 2.0], [13, -4.0, -1.0, -1.0, 1.0], [33, 5.0, -1.0, 6.0, 0.0], [31, -4.0, -2.0, -1.0, -1.0]]], [[[10, 13]], [], 4]]], [[[[[18, -3.0, 3.0, -1.0, 4.0], [34, 1.0, -4.0, 1.0, -2.0], [23, 4.0, -2.0, 7.0, 1.0]], [[18, -3.0, 3.0, -1.0, 4.0], [34, 3.0, -4.0, 3.0, -2.0], [23, 3.0, -2.0, 6.0, 1.0]]], [[[23, 34]], [], 1]], [[[[30, 5.0, 4.0, 7.0, 7.0], [13, -5.0, 1.0, -5.0, 2.0], [35, -3.0, 0.0, -1.0, 0.0], [14, -5.0, 3.0, -5.0, 5.0]], [[30, 2.0, 5.0, 4.0, 8.0], [13, -4.0, 0.0, -4.0, 1.0], [35, -2.0, 0.0, 0.0, 0.0], [14, -5.0, 3.0, -5.0, 5.0]]], [[], [[13, 14]], 3]], [[[[8, -1.0, -1.0, -1.0, -1.0], [9, 4.0, 0.0, 4.0, 3.0], [30, -3.0, 5.0, -1.0, 5.0], [32, 0.0, 2.0, 1.0, 5.0], [3, -3.0, 1.0, 0.0, 1.0], [18, -2.0, 4.0, -2.0, 7.0], [23, 5.0, 2.0, 5.0, 2.0], [39, -4.0, 4.0, -1.0, 5.0]], [[8, 0.0, -1.0, 0.0, -1.0], [9, 1.0, -1.0, 1.0, 2.0], [30, -6.0, 4.0, -4.0, 4.0], [32, -1.0, 1.0, 0.0, 4.0], [3, -3.0, 2.0, 0.0, 2.0], [18, -3.0, 4.0, -3.0, 7.0], [23, 5.0, 1.0, 5.0, 1.0], [39, -4.0, 3.0, -1.0, 4.0]]], [[[32, 39]], [[3, 30], [8, 30], [8, 39], [18, 30]], 12]], [[[[15, -4.0, 5.0, -1.0, 6.0], [21, -2.0, 1.0, -1.0, 2.0], [16, 5.0, 2.0, 8.0, 3.0], [39, 1.0, 1.0, 4.0, 1.0], [27, 1.0, -3.0, 1.0, -2.0], [12, 5.0, -5.0, 8.0, -5.0]], [[15, -4.0, 4.0, -1.0, 5.0], [21, -1.0, 1.0, 0.0, 2.0], [16, 6.0, 2.0, 9.0, 3.0], [39, 3.0, 1.0, 6.0, 1.0], [27, 3.0, -3.0, 3.0, -2.0], [12, 5.0, -5.0, 8.0, -5.0]]], [[], [], 2]], [[[[33, -3.0, 1.0, -1.0, 2.0], [4, 1.0, -5.0, 4.0, -4.0], [36, -4.0, 2.0, -3.0, 5.0]], [[33, -2.0, 2.0, 0.0, 3.0], [4, -2.0, -5.0, 1.0, -4.0], [36, -2.0, 1.0, -1.0, 4.0]]], [[], [], 2]], [[[[12, 2.0, -4.0, 5.0, -1.0], [4, 5.0, 0.0, 6.0, 0.0], [19, -5.0, -2.0, -4.0, -1.0], [16, -1.0, -3.0, 0.0, 0.0], [22, 5.0, 2.0, 5.0, 3.0]], [[12, 3.0, -5.0, 6.0, -2.0], [4, 5.0, 0.0, 6.0, 0.0], [19, -3.0, -2.0, -2.0, -1.0], [16, -4.0, -2.0, -3.0, 1.0], [22, 9.0, 3.0, 9.0, 4.0]]], [[[16, 19]], [[4, 22], [12, 22]], 6]], [[[[21, -1.0, 3.0, -1.0, 3.0], [13, -2.0, 1.0, 1.0, 1.0], [33, 4.0, -2.0, 7.0, 0.0], [39, 1.0, -3.0, 2.0, -3.0]], [[21, 0.0, 3.0, 0.0, 3.0], [13, -2.0, 2.0, 1.0, 2.0], [33, 6.0, -3.0, 9.0, -1.0], [39, 2.0, -4.0, 3.0, -4.0]]], [[], [[13, 39]], 1]], [[[[8, 5.0, 2.0, 6.0, 2.0], [5, -3.0, -5.0, -1.0, -4.0], [27, 0.0, 1.0, 1.0, 1.0], [16, 4.0, 2.0, 6.0, 3.0], [38, 5.0, -4.0, 8.0, -2.0], [19, -5.0, 2.0, -5.0, 5.0], [20, 1.0, 1.0, 3.0, 1.0], [31, 5.0, -1.0, 8.0, 2.0], [22, -2.0, -4.0, -2.0, -2.0]], [[8, 5.0, 3.0, 6.0, 3.0], [5, -3.0, -5.0, -1.0, -4.0], [27, 2.0, 2.0, 3.0, 2.0], [16, 1.0, 2.0, 3.0, 3.0], [38, 7.0, -3.0, 10.0, -1.0], [19, -5.0, 3.0, -5.0, 6.0], [20, 2.0, 1.0, 4.0, 1.0], [31, 9.0, 0.0, 12.0, 3.0], [22, 0.0, -3.0, 0.0, -1.0]]], [[[16, 27]], [[5, 22], [8, 16], [8, 31], [8, 38], [16, 31], [16, 38]], 15]]], [[[[[24, -3.0, 5.0, -1.0, 5.0], [29, -4.0, -1.0, -2.0, 0.0], [15, -4.0, -4.0, -4.0, -3.0], [6, 1.0, -2.0, 2.0, 1.0], [11, 4.0, 5.0, 7.0, 6.0], [13, 1.0, 5.0, 4.0, 5.0], [14, 1.0, -5.0, 4.0, -4.0], [19, 5.0, 5.0, 7.0, 6.0], [16, 5.0, 4.0, 5.0, 4.0]], [[24, -3.0, 5.0, -1.0, 5.0], [29, -5.0, -1.0, -3.0, 0.0], [15, 0.0, -4.0, 0.0, -3.0], [6, 1.0, -3.0, 2.0, 0.0], [11, 4.0, 6.0, 7.0, 7.0], [13, 2.0, 5.0, 5.0, 5.0], [14, 5.0, -5.0, 8.0, -4.0], [19, 5.0, 4.0, 7.0, 5.0], [16, 5.0, 4.0, 5.0, 4.0]]], [[[13, 19]], [[6, 14], [15, 24], [15, 29]], 16]], [[[[23, 3.0, 0.0, 6.0, 0.0], [25, -3.0, -1.0, 0.0, 2.0], [7, -3.0, 1.0, 0.0, 1.0], [21, -5.0, 4.0, -2.0, 6.0], [37, 5.0, 1.0, 5.0, 3.0], [30, -3.0, -1.0, -2.0, 1.0], [26, -3.0, 3.0, 0.0, 5.0], [5, -5.0, 3.0, -3.0, 5.0]], [[23, 2.0, -1.0, 5.0, -1.0], [25, -3.0, -1.0, 0.0, 2.0], [7, -6.0, 2.0, -3.0, 2.0], [21, -5.0, 4.0, -2.0, 6.0], [37, 5.0, 1.0, 5.0, 3.0], [30, -4.0, -1.0, -3.0, 1.0], [26, -2.0, 2.0, 1.0, 4.0], [5, -5.0, 2.0, -3.0, 4.0]]], [[], [[5, 26], [7, 26], [26, 30]], 9]], [[[[33, -1.0, -1.0, 2.0, 1.0], [8, 2.0, -3.0, 4.0, -1.0], [26, 4.0, 3.0, 6.0, 6.0], [17, -5.0, 4.0, -4.0, 6.0]], [[33, -2.0, -1.0, 1.0, 1.0], [8, 4.0, -4.0, 6.0, -2.0], [26, 1.0, 3.0, 3.0, 6.0], [17, -6.0, 4.0, -5.0, 6.0]]], [[], [[8, 26], [8, 33]], 5]], [[[[28, 2.0, 2.0, 5.0, 2.0], [24, -3.0, 4.0, -3.0, 4.0], [29, -5.0, 4.0, -4.0, 5.0], [10, 1.0, 1.0, 4.0, 2.0], [33, -2.0, -4.0, -1.0, -3.0], [12, 2.0, 3.0, 2.0, 3.0], [39, -5.0, -3.0, -2.0, -2.0], [1, 3.0, -5.0, 4.0, -4.0]], [[28, 2.0, 2.0, 5.0, 2.0], [24, -4.0, 5.0, -4.0, 5.0], [29, -6.0, 3.0, -5.0, 4.0], [10, 3.0, 1.0, 6.0, 2.0], [33, -3.0, -4.0, -2.0, -3.0], [12, 4.0, 3.0, 4.0, 3.0], [39, -3.0, -2.0, 0.0, -1.0], [1, 2.0, -5.0, 3.0, -4.0]]], [[], [[1, 12], [24, 39], [29, 39]], 12]], [[[[23, 1.0, 0.0, 2.0, 1.0], [30, 5.0, -2.0, 5.0, -1.0], [16, 3.0, 5.0, 6.0, 8.0], [2, -3.0, 2.0, 0.0, 2.0]], [[23, 0.0, 0.0, 1.0, 1.0], [30, 7.0, -2.0, 7.0, -1.0], [16, 5.0, 4.0, 8.0, 7.0], [2, -6.0, 3.0, -3.0, 3.0]]], [[], [], 0]], [[[[28, 0.0, -4.0, 2.0, -4.0], [20, 2.0, -5.0, 2.0, -3.0]], [[28, 4.0, -3.0, 6.0, -3.0], [20, 2.0, -5.0, 2.0, -3.0]]], [[], [[20, 28]], 2]], [[[[10, -5.0, -1.0, -3.0, -1.0], [17, 3.0, 4.0, 6.0, 6.0], [30, 0.0, -1.0, 0.0, -1.0], [25, 2.0, -4.0, 3.0, -4.0], [39, -2.0, 3.0, -2.0, 6.0]], [[10, -5.0, -2.0, -3.0, -2.0], [17, 3.0, 4.0, 6.0, 6.0], [30, 0.0, -1.0, 0.0, -1.0], [25, 2.0, -4.0, 3.0, -4.0], [39, -3.0, 3.0, -3.0, 6.0]]], [[], [], 1]], [[[[7, 1.0, 5.0, 1.0, 8.0], [12, -1.0, -4.0, 1.0, -1.0], [4, -3.0, -4.0, -2.0, -3.0], [26, 4.0, 5.0, 4.0, 5.0], [19, -4.0, -2.0, -4.0, 0.0], [6, 5.0, 3.0, 7.0, 3.0], [5, -1.0, 2.0, -1.0, 4.0], [30, 4.0, 0.0, 5.0, 0.0]], [[7, 1.0, 5.0, 1.0, 8.0], [12, -1.0, -4.0, 1.0, -1.0], [4, -3.0, -5.0, -2.0, -4.0], [26, 4.0, 5.0, 4.0, 5.0], [19, -4.0, -3.0, -4.0, -1.0], [6, 9.0, 2.0, 11.0, 2.0], [5, -2.0, 3.0, -2.0, 5.0], [30, 5.0, 1.0, 6.0, 1.0]]], [[], [[5, 12], [6, 30], [26, 30]], 4]]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("case %d" % i, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
case 0	`[[], [[19, 19], [19, 27], [19, 38], [21, 27], [27, 27], [27, 38]], 11]`	`[[], [[19, 38], [21, 27], [27, 38]], 9]`	Failed
case 1	`[[], [[11, 28], [18, 18], [18, 21], [18, 33], [21, 33], [22, 28]], 12]`	`[[], [[18, 33], [21, 33]], 8]`	Failed
case 2	`[[], [[30, 30], [36, 36]], 2]`	`[[], [], 0]`	Failed
case 3	`[[], [[1, 3]], 1]`	`[[], [], 0]`	Failed
case 4	`[[], [], 0]`	`[[], [], 0]`	Passed
case 5	`[[], [[20, 29], [29, 36]], 2]`	`[[], [[20, 29], [29, 36]], 3]`	Failed
case 6	`[[], [[5, 12], [5, 33], [32, 32]], 6]`	`[[], [[5, 12], [5, 33]], 5]`	Failed
case 7	`[[], [[1, 1], [16, 16], [16, 19]], 5]`	`[[[19, 21]], [[16, 19]], 4]`	Failed

SHA-256 / eab85b27385f8b5273bde67f0cf4de943218cf8464972d97dedc5b8428cb81b7

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(prev, curr):
    old = {b[0]: b for b in prev}
    new = {b[0]: b for b in curr}
    E = []
    for i, b in old.items():
        E.append([b[1], 0, i])
        E.append([b[3], 1, i])
    E.sort()
    for e in E:
        b = new[e[2]]
        e[0] = b[1] if e[1] == 0 else b[3]
    def yover(a, c):
        return new[a][2] <= new[c][4] and new[c][2] <= new[a][4]
    begins, ends = set(), set()
    swaps = 0
    for i in range(1, len(E)):
        j = i
        while j > 0 and (E[j - 1][0], E[j - 1][1]) > (E[j][0], E[j][1]):
            e, f = E[j], E[j - 1]
            E[j - 1], E[j] = e, f
            swaps += 1
            p = (min(e[2], f[2]), max(e[2], f[2]))
            if e[1] == 0 and f[1] == 1:
                if yover(e[2], f[2]):
                    begins.add(p)
            elif e[1] == 1 and f[1] == 0:
                ends.add(p)
            j -= 1
    return [sorted(list(p) for p in begins), sorted(list(p) for p in ends), swaps]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[[[38, -5.0, 2.0, -4.0, 4.0], [19, -4.0, 5.0, -4.0, 5.0], [27, -2.0, -5.0, -2.0, -3.0], [21, -2.0, -2.0, 1.0, 0.0], [12, 2.0, -5.0, 5.0, -3.0]], [[38, -1.0, 3.0, 0.0, 5.0], [19, -5.0, 5.0, -5.0, 5.0], [27, -5.0, -4.0, -5.0, -2.0], [21, 2.0, -3.0, 5.0, -1.0], [12, 6.0, -4.0, 9.0, -2.0]]], [[], [[19, 38], [21, 27], [27, 38]], 9]], [[[[22, 2.0, 1.0, 3.0, 1.0], [28, 3.0, 0.0, 4.0, 0.0], [21, -2.0, -2.0, 1.0, -1.0], [33, -1.0, 1.0, 0.0, 2.0], [11, 2.0, 5.0, 5.0, 5.0], [18, -1.0, 1.0, -1.0, 1.0]], [[22, 6.0, 1.0, 7.0, 1.0], [28, 5.0, 0.0, 6.0, 0.0], [21, 0.0, -3.0, 3.0, -2.0], [33, -4.0, 1.0, -3.0, 2.0], [11, 6.0, 5.0, 9.0, 5.0], [18, 0.0, 2.0, 0.0, 2.0]]], [[], [[18, 33], [21, 33]], 8]], [[[[36, 4.0, -3.0, 4.0, -2.0], [30, 5.0, 1.0, 5.0, 1.0]], [[36, 4.0, -3.0, 4.0, -2.0], [30, 5.0, 1.0, 5.0, 1.0]]], [[], [], 0]], [[[[3, 3.0, 0.0, 4.0, 3.0], [1, 4.0, -1.0, 6.0, 1.0]], [[3, 0.0, 1.0, 1.0, 4.0], [1, 1.0, -1.0, 3.0, 1.0]]], [[], [], 0]], [[[[5, -4.0, -1.0, -2.0, 0.0], [15, 2.0, -2.0, 5.0, -2.0]], [[5, -4.0, -1.0, -2.0, 0.0], [15, 1.0, -3.0, 4.0, -3.0]]], [[], [], 0]], [[[[20, 1.0, -3.0, 4.0, -3.0], [8, -4.0, -2.0, -2.0, 1.0], [29, 1.0, 2.0, 4.0, 4.0], [36, 0.0, 4.0, 2.0, 7.0]], [[20, 1.0, -2.0, 4.0, -2.0], [8, -2.0, -1.0, 0.0, 2.0], [29, 5.0, 2.0, 8.0, 4.0], [36, 0.0, 5.0, 2.0, 8.0]]], [[], [[20, 29], [29, 36]], 3]], [[[[32, -2.0, -1.0, -2.0, 2.0], [33, 1.0, -4.0, 2.0, -2.0], [12, 3.0, 1.0, 5.0, 2.0], [5, 1.0, 5.0, 3.0, 7.0]], [[32, -1.0, -1.0, -1.0, 2.0], [33, 1.0, -5.0, 2.0, -3.0], [12, 7.0, 1.0, 9.0, 2.0], [5, -2.0, 6.0, 0.0, 8.0]]], [[], [[5, 12], [5, 33]], 5]], [[[[21, -2.0, -5.0, 1.0, -5.0], [19, 3.0, -5.0, 5.0, -4.0], [36, -2.0, -1.0, 0.0, 0.0], [16, 5.0, -1.0, 5.0, 0.0], [1, -3.0, 3.0, -3.0, 4.0]], [[21, -1.0, -5.0, 2.0, -5.0], [19, 2.0, -6.0, 4.0, -5.0], [36, -2.0, 0.0, 0.0, 1.0], [16, 9.0, -1.0, 9.0, 0.0], [1, -3.0, 3.0, -3.0, 4.0]]], [[[19, 21]], [[16, 19]], 4]]], [[[[[6, 5.0, 4.0, 5.0, 7.0], [38, -3.0, 0.0, 0.0, 3.0], [18, -5.0, -3.0, -4.0, -2.0], [9, -5.0, 5.0, -5.0, 7.0], [27, 0.0, 4.0, 1.0, 6.0]], [[6, 7.0, 4.0, 7.0, 7.0], [38, -3.0, 0.0, 0.0, 3.0], [18, -4.0, -3.0, -3.0, -2.0], [9, -5.0, 5.0, -5.0, 7.0], [27, -1.0, 4.0, 0.0, 6.0]]], [[], [[9, 18]], 2]], [[[[31, 1.0, 0.0, 1.0, 0.0], [38, -4.0, 1.0, -2.0, 4.0], [5, -1.0, -1.0, 0.0, -1.0], [39, 2.0, -3.0, 5.0, -3.0], [27, 3.0, 2.0, 3.0, 5.0], [4, -4.0, -1.0, -3.0, 2.0]], [[31, 1.0, 1.0, 1.0, 1.0], [38, -2.0, 1.0, 0.0, 4.0], [5, 1.0, -1.0, 2.0, -1.0], [39, 6.0, -3.0, 9.0, -3.0], [27, 0.0, 1.0, 0.0, 4.0], [4, -4.0, -1.0, -3.0, 2.0]]], [[[27, 31], [27, 38]], [[4, 38], [5, 27], [27, 31], [27, 39]], 14]], [[[[37, -1.0, -5.0, 1.0, -3.0], [39, -3.0, 0.0, -2.0, 2.0], [12, 1.0, -5.0, 4.0, -3.0], [1, -4.0, -4.0, -2.0, -2.0], [16, 1.0, -3.0, 2.0, 0.0]], [[37, 0.0, -4.0, 2.0, -2.0], [39, -3.0, -1.0, -2.0, 1.0], [12, -2.0, -4.0, 1.0, -2.0], [1, -3.0, -3.0, -1.0, -1.0], [16, 0.0, -2.0, 1.0, 1.0]]], [[[1, 12]], [], 6]], [[[[34, -5.0, 5.0, -3.0, 6.0], [25, 3.0, -4.0, 6.0, -1.0], [10, -5.0, -3.0, -4.0, -2.0], [2, -4.0, 0.0, -2.0, 0.0], [13, -3.0, 5.0, -3.0, 6.0], [3, -1.0, 2.0, 0.0, 2.0], [20, 1.0, -4.0, 1.0, -3.0]], [[34, -6.0, 4.0, -4.0, 5.0], [25, 3.0, -4.0, 6.0, -1.0], [10, -5.0, -2.0, -4.0, -1.0], [2, -3.0, -1.0, -1.0, -1.0], [13, -1.0, 4.0, -1.0, 5.0], [3, 3.0, 2.0, 4.0, 2.0], [20, 0.0, -4.0, 0.0, -3.0]]], [[], [[2, 10], [2, 34], [3, 20], [13, 34]], 10]], [[[[10, 0.0, -5.0, 1.0, -5.0], [12, -3.0, -3.0, 0.0, -2.0]], [[10, 1.0, -5.0, 2.0, -5.0], [12, -2.0, -2.0, 1.0, -1.0]]], [[], [], 0]], [[[[13, -2.0, 1.0, -1.0, 2.0], [20, -5.0, 0.0, -4.0, 1.0], [37, 0.0, 5.0, 3.0, 8.0], [8, 5.0, -3.0, 5.0, -2.0], [2, 3.0, -1.0, 6.0, 0.0]], [[13, -3.0, 1.0, -2.0, 2.0], [20, -6.0, -1.0, -5.0, 0.0], [37, 4.0, 6.0, 7.0, 9.0], [8, 5.0, -2.0, 5.0, -1.0], [2, 2.0, -1.0, 5.0, 0.0]]], [[], [], 4]], [[[[24, -1.0, -2.0, 2.0, 1.0], [30, 0.0, -3.0, 3.0, -2.0], [37, -5.0, 1.0, -5.0, 4.0], [18, 1.0, 2.0, 2.0, 4.0], [26, -3.0, -4.0, -2.0, -3.0], [29, 3.0, 2.0, 5.0, 4.0]], [[24, -2.0, -3.0, 1.0, 0.0], [30, 0.0, -2.0, 3.0, -1.0], [37, -4.0, 0.0, -4.0, 3.0], [18, 5.0, 3.0, 6.0, 5.0], [26, -3.0, -4.0, -2.0, -3.0], [29, 3.0, 2.0, 5.0, 4.0]]], [[[18, 29], [24, 26]], [[18, 24], [18, 30]], 8]], [[[[25, -3.0, 5.0, -1.0, 8.0], [9, -1.0, -4.0, 0.0, -3.0], [21, 0.0, -1.0, 3.0, 0.0], [3, 0.0, 3.0, 0.0, 5.0], [4, 4.0, -2.0, 6.0, -2.0]], [[25, -3.0, 4.0, -1.0, 7.0], [9, 1.0, -4.0, 2.0, -3.0], [21, 2.0, -2.0, 5.0, -1.0], [3, 0.0, 4.0, 0.0, 6.0], [4, 4.0, -2.0, 6.0, -2.0]]], [[[4, 21]], [[3, 9], [3, 21], [9, 25]], 5]]], [[[[[3, 5.0, 4.0, 6.0, 7.0], [21, 4.0, 2.0, 6.0, 2.0], [35, 4.0, -3.0, 6.0, 0.0], [14, -4.0, -5.0, -4.0, -5.0], [31, -2.0, 2.0, -1.0, 2.0], [20, 5.0, 3.0, 8.0, 5.0], [34, 1.0, 5.0, 2.0, 6.0]], [[3, 4.0, 4.0, 5.0, 7.0], [21, 5.0, 2.0, 7.0, 2.0], [35, 5.0, -3.0, 7.0, 0.0], [14, -2.0, -5.0, -2.0, -5.0], [31, -2.0, 3.0, -1.0, 3.0], [20, 5.0, 2.0, 8.0, 4.0], [34, 1.0, 6.0, 2.0, 7.0]]], [[], [], 3]], [[[[25, -4.0, 3.0, -4.0, 5.0], [8, -1.0, 1.0, 2.0, 2.0], [15, -3.0, 4.0, 0.0, 4.0]], [[25, -3.0, 2.0, -3.0, 4.0], [8, -2.0, 1.0, 1.0, 2.0], [15, 1.0, 5.0, 4.0, 5.0]]], [[], [], 2]], [[[[3, -5.0, -3.0, -3.0, 0.0], [10, 1.0, 3.0, 3.0, 4.0], [38, -5.0, 5.0, -4.0, 6.0]], [[3, -8.0, -2.0, -6.0, 1.0], [10, -2.0, 4.0, 0.0, 5.0], [38, -4.0, 5.0, -3.0, 6.0]]], [[], [[3, 38]], 2]], [[[[20, -5.0, -1.0, -5.0, 2.0], [7, 3.0, 0.0, 5.0, 1.0]], [[20, -5.0, -1.0, -5.0, 2.0], [7, 7.0, 0.0, 9.0, 1.0]]], [[], [], 0]], [[[[11, -2.0, -1.0, -2.0, 0.0], [14, 1.0, -4.0, 2.0, -3.0], [32, 5.0, 3.0, 6.0, 4.0], [6, -2.0, 5.0, 1.0, 8.0], [39, 0.0, -4.0, 1.0, -3.0], [8, -1.0, -3.0, 2.0, 0.0]], [[11, -5.0, 0.0, -5.0, 1.0], [14, 2.0, -5.0, 3.0, -4.0], [32, 5.0, 2.0, 6.0, 3.0], [6, 2.0, 4.0, 5.0, 7.0], [39, 0.0, -4.0, 1.0, -3.0], [8, 0.0, -3.0, 3.0, 0.0]]], [[], [[6, 11], [6, 39], [14, 39]], 10]], [[[[38, -3.0, -5.0, -3.0, -4.0], [10, 4.0, 1.0, 6.0, 3.0], [15, 1.0, 0.0, 3.0, 3.0], [23, -4.0, -2.0, -1.0, 0.0], [24, -1.0, 3.0, 2.0, 4.0], [14, 3.0, -4.0, 5.0, -3.0], [26, -2.0, 3.0, 1.0, 5.0], [20, -5.0, 4.0, -4.0, 5.0]], [[38, -6.0, -6.0, -6.0, -5.0], [10, 1.0, 0.0, 3.0, 2.0], [15, 1.0, 1.0, 3.0, 4.0], [23, 0.0, -2.0, 3.0, 0.0], [24, 0.0, 2.0, 3.0, 3.0], [14, 5.0, -5.0, 7.0, -4.0], [26, -2.0, 2.0, 1.0, 4.0], [20, -3.0, 5.0, -2.0, 6.0]]], [[[10, 15], [10, 23], [10, 24], [10, 26]], [[10, 14], [14, 15], [20, 23], [20, 38], [23, 38]], 19]], [[[[3, 1.0, -5.0, 2.0, -5.0], [32, 2.0, -5.0, 3.0, -3.0], [38, -3.0, 5.0, -1.0, 5.0], [1, 2.0, 3.0, 4.0, 3.0], [13, -3.0, -4.0, 0.0, -3.0]], [[3, 2.0, -4.0, 3.0, -4.0], [32, 2.0, -5.0, 3.0, -3.0], [38, -3.0, 5.0, -1.0, 5.0], [1, 3.0, 2.0, 5.0, 2.0], [13, -3.0, -5.0, 0.0, -4.0]]], [[], [], 1]], [[[[7, -2.0, -1.0, 0.0, 0.0], [10, -5.0, 1.0, -5.0, 2.0], [13, -4.0, 0.0, -1.0, 2.0], [33, 5.0, -1.0, 6.0, 0.0], [31, -4.0, -1.0, -1.0, 0.0]], [[7, -1.0, -1.0, 1.0, 0.0], [10, -3.0, 1.0, -3.0, 2.0], [13, -4.0, -1.0, -1.0, 1.0], [33, 5.0, -1.0, 6.0, 0.0], [31, -4.0, -2.0, -1.0, -1.0]]], [[[10, 13]], [], 4]]], [[[[[18, -3.0, 3.0, -1.0, 4.0], [34, 1.0, -4.0, 1.0, -2.0], [23, 4.0, -2.0, 7.0, 1.0]], [[18, -3.0, 3.0, -1.0, 4.0], [34, 3.0, -4.0, 3.0, -2.0], [23, 3.0, -2.0, 6.0, 1.0]]], [[[23, 34]], [], 1]], [[[[30, 5.0, 4.0, 7.0, 7.0], [13, -5.0, 1.0, -5.0, 2.0], [35, -3.0, 0.0, -1.0, 0.0], [14, -5.0, 3.0, -5.0, 5.0]], [[30, 2.0, 5.0, 4.0, 8.0], [13, -4.0, 0.0, -4.0, 1.0], [35, -2.0, 0.0, 0.0, 0.0], [14, -5.0, 3.0, -5.0, 5.0]]], [[], [[13, 14]], 3]], [[[[8, -1.0, -1.0, -1.0, -1.0], [9, 4.0, 0.0, 4.0, 3.0], [30, -3.0, 5.0, -1.0, 5.0], [32, 0.0, 2.0, 1.0, 5.0], [3, -3.0, 1.0, 0.0, 1.0], [18, -2.0, 4.0, -2.0, 7.0], [23, 5.0, 2.0, 5.0, 2.0], [39, -4.0, 4.0, -1.0, 5.0]], [[8, 0.0, -1.0, 0.0, -1.0], [9, 1.0, -1.0, 1.0, 2.0], [30, -6.0, 4.0, -4.0, 4.0], [32, -1.0, 1.0, 0.0, 4.0], [3, -3.0, 2.0, 0.0, 2.0], [18, -3.0, 4.0, -3.0, 7.0], [23, 5.0, 1.0, 5.0, 1.0], [39, -4.0, 3.0, -1.0, 4.0]]], [[[32, 39]], [[3, 30], [8, 30], [8, 39], [18, 30]], 12]], [[[[15, -4.0, 5.0, -1.0, 6.0], [21, -2.0, 1.0, -1.0, 2.0], [16, 5.0, 2.0, 8.0, 3.0], [39, 1.0, 1.0, 4.0, 1.0], [27, 1.0, -3.0, 1.0, -2.0], [12, 5.0, -5.0, 8.0, -5.0]], [[15, -4.0, 4.0, -1.0, 5.0], [21, -1.0, 1.0, 0.0, 2.0], [16, 6.0, 2.0, 9.0, 3.0], [39, 3.0, 1.0, 6.0, 1.0], [27, 3.0, -3.0, 3.0, -2.0], [12, 5.0, -5.0, 8.0, -5.0]]], [[], [], 2]], [[[[33, -3.0, 1.0, -1.0, 2.0], [4, 1.0, -5.0, 4.0, -4.0], [36, -4.0, 2.0, -3.0, 5.0]], [[33, -2.0, 2.0, 0.0, 3.0], [4, -2.0, -5.0, 1.0, -4.0], [36, -2.0, 1.0, -1.0, 4.0]]], [[], [], 2]], [[[[12, 2.0, -4.0, 5.0, -1.0], [4, 5.0, 0.0, 6.0, 0.0], [19, -5.0, -2.0, -4.0, -1.0], [16, -1.0, -3.0, 0.0, 0.0], [22, 5.0, 2.0, 5.0, 3.0]], [[12, 3.0, -5.0, 6.0, -2.0], [4, 5.0, 0.0, 6.0, 0.0], [19, -3.0, -2.0, -2.0, -1.0], [16, -4.0, -2.0, -3.0, 1.0], [22, 9.0, 3.0, 9.0, 4.0]]], [[[16, 19]], [[4, 22], [12, 22]], 6]], [[[[21, -1.0, 3.0, -1.0, 3.0], [13, -2.0, 1.0, 1.0, 1.0], [33, 4.0, -2.0, 7.0, 0.0], [39, 1.0, -3.0, 2.0, -3.0]], [[21, 0.0, 3.0, 0.0, 3.0], [13, -2.0, 2.0, 1.0, 2.0], [33, 6.0, -3.0, 9.0, -1.0], [39, 2.0, -4.0, 3.0, -4.0]]], [[], [[13, 39]], 1]], [[[[8, 5.0, 2.0, 6.0, 2.0], [5, -3.0, -5.0, -1.0, -4.0], [27, 0.0, 1.0, 1.0, 1.0], [16, 4.0, 2.0, 6.0, 3.0], [38, 5.0, -4.0, 8.0, -2.0], [19, -5.0, 2.0, -5.0, 5.0], [20, 1.0, 1.0, 3.0, 1.0], [31, 5.0, -1.0, 8.0, 2.0], [22, -2.0, -4.0, -2.0, -2.0]], [[8, 5.0, 3.0, 6.0, 3.0], [5, -3.0, -5.0, -1.0, -4.0], [27, 2.0, 2.0, 3.0, 2.0], [16, 1.0, 2.0, 3.0, 3.0], [38, 7.0, -3.0, 10.0, -1.0], [19, -5.0, 3.0, -5.0, 6.0], [20, 2.0, 1.0, 4.0, 1.0], [31, 9.0, 0.0, 12.0, 3.0], [22, 0.0, -3.0, 0.0, -1.0]]], [[[16, 27]], [[5, 22], [8, 16], [8, 31], [8, 38], [16, 31], [16, 38]], 15]]], [[[[[24, -3.0, 5.0, -1.0, 5.0], [29, -4.0, -1.0, -2.0, 0.0], [15, -4.0, -4.0, -4.0, -3.0], [6, 1.0, -2.0, 2.0, 1.0], [11, 4.0, 5.0, 7.0, 6.0], [13, 1.0, 5.0, 4.0, 5.0], [14, 1.0, -5.0, 4.0, -4.0], [19, 5.0, 5.0, 7.0, 6.0], [16, 5.0, 4.0, 5.0, 4.0]], [[24, -3.0, 5.0, -1.0, 5.0], [29, -5.0, -1.0, -3.0, 0.0], [15, 0.0, -4.0, 0.0, -3.0], [6, 1.0, -3.0, 2.0, 0.0], [11, 4.0, 6.0, 7.0, 7.0], [13, 2.0, 5.0, 5.0, 5.0], [14, 5.0, -5.0, 8.0, -4.0], [19, 5.0, 4.0, 7.0, 5.0], [16, 5.0, 4.0, 5.0, 4.0]]], [[[13, 19]], [[6, 14], [15, 24], [15, 29]], 16]], [[[[23, 3.0, 0.0, 6.0, 0.0], [25, -3.0, -1.0, 0.0, 2.0], [7, -3.0, 1.0, 0.0, 1.0], [21, -5.0, 4.0, -2.0, 6.0], [37, 5.0, 1.0, 5.0, 3.0], [30, -3.0, -1.0, -2.0, 1.0], [26, -3.0, 3.0, 0.0, 5.0], [5, -5.0, 3.0, -3.0, 5.0]], [[23, 2.0, -1.0, 5.0, -1.0], [25, -3.0, -1.0, 0.0, 2.0], [7, -6.0, 2.0, -3.0, 2.0], [21, -5.0, 4.0, -2.0, 6.0], [37, 5.0, 1.0, 5.0, 3.0], [30, -4.0, -1.0, -3.0, 1.0], [26, -2.0, 2.0, 1.0, 4.0], [5, -5.0, 2.0, -3.0, 4.0]]], [[], [[5, 26], [7, 26], [26, 30]], 9]], [[[[33, -1.0, -1.0, 2.0, 1.0], [8, 2.0, -3.0, 4.0, -1.0], [26, 4.0, 3.0, 6.0, 6.0], [17, -5.0, 4.0, -4.0, 6.0]], [[33, -2.0, -1.0, 1.0, 1.0], [8, 4.0, -4.0, 6.0, -2.0], [26, 1.0, 3.0, 3.0, 6.0], [17, -6.0, 4.0, -5.0, 6.0]]], [[], [[8, 26], [8, 33]], 5]], [[[[28, 2.0, 2.0, 5.0, 2.0], [24, -3.0, 4.0, -3.0, 4.0], [29, -5.0, 4.0, -4.0, 5.0], [10, 1.0, 1.0, 4.0, 2.0], [33, -2.0, -4.0, -1.0, -3.0], [12, 2.0, 3.0, 2.0, 3.0], [39, -5.0, -3.0, -2.0, -2.0], [1, 3.0, -5.0, 4.0, -4.0]], [[28, 2.0, 2.0, 5.0, 2.0], [24, -4.0, 5.0, -4.0, 5.0], [29, -6.0, 3.0, -5.0, 4.0], [10, 3.0, 1.0, 6.0, 2.0], [33, -3.0, -4.0, -2.0, -3.0], [12, 4.0, 3.0, 4.0, 3.0], [39, -3.0, -2.0, 0.0, -1.0], [1, 2.0, -5.0, 3.0, -4.0]]], [[], [[1, 12], [24, 39], [29, 39]], 12]], [[[[23, 1.0, 0.0, 2.0, 1.0], [30, 5.0, -2.0, 5.0, -1.0], [16, 3.0, 5.0, 6.0, 8.0], [2, -3.0, 2.0, 0.0, 2.0]], [[23, 0.0, 0.0, 1.0, 1.0], [30, 7.0, -2.0, 7.0, -1.0], [16, 5.0, 4.0, 8.0, 7.0], [2, -6.0, 3.0, -3.0, 3.0]]], [[], [], 0]], [[[[28, 0.0, -4.0, 2.0, -4.0], [20, 2.0, -5.0, 2.0, -3.0]], [[28, 4.0, -3.0, 6.0, -3.0], [20, 2.0, -5.0, 2.0, -3.0]]], [[], [[20, 28]], 2]], [[[[10, -5.0, -1.0, -3.0, -1.0], [17, 3.0, 4.0, 6.0, 6.0], [30, 0.0, -1.0, 0.0, -1.0], [25, 2.0, -4.0, 3.0, -4.0], [39, -2.0, 3.0, -2.0, 6.0]], [[10, -5.0, -2.0, -3.0, -2.0], [17, 3.0, 4.0, 6.0, 6.0], [30, 0.0, -1.0, 0.0, -1.0], [25, 2.0, -4.0, 3.0, -4.0], [39, -3.0, 3.0, -3.0, 6.0]]], [[], [], 1]], [[[[7, 1.0, 5.0, 1.0, 8.0], [12, -1.0, -4.0, 1.0, -1.0], [4, -3.0, -4.0, -2.0, -3.0], [26, 4.0, 5.0, 4.0, 5.0], [19, -4.0, -2.0, -4.0, 0.0], [6, 5.0, 3.0, 7.0, 3.0], [5, -1.0, 2.0, -1.0, 4.0], [30, 4.0, 0.0, 5.0, 0.0]], [[7, 1.0, 5.0, 1.0, 8.0], [12, -1.0, -4.0, 1.0, -1.0], [4, -3.0, -5.0, -2.0, -4.0], [26, 4.0, 5.0, 4.0, 5.0], [19, -4.0, -3.0, -4.0, -1.0], [6, 9.0, 2.0, 11.0, 2.0], [5, -2.0, 3.0, -2.0, 5.0], [30, 5.0, 1.0, 6.0, 1.0]]], [[], [[5, 12], [6, 30], [26, 30]], 4]]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("case %d" % i, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
case 0	`[[], [[19, 38], [21, 27], [27, 38]], 9]`	`[[], [[19, 38], [21, 27], [27, 38]], 9]`	Passed
case 1	`[[], [[18, 33], [21, 33]], 8]`	`[[], [[18, 33], [21, 33]], 8]`	Passed
case 2	`[[], [], 0]`	`[[], [], 0]`	Passed
case 3	`[[], [], 0]`	`[[], [], 0]`	Passed
case 4	`[[], [], 0]`	`[[], [], 0]`	Passed
case 5	`[[], [[20, 29], [29, 36]], 3]`	`[[], [[20, 29], [29, 36]], 3]`	Passed
case 6	`[[], [[5, 12], [5, 33]], 5]`	`[[], [[5, 12], [5, 33]], 5]`	Passed
case 7	`[[[19, 21]], [[16, 19]], 4]`	`[[[19, 21]], [[16, 19]], 4]`	Passed

SHA-256 / 067b1db2f90ed9b6304cedee0af3a149f2bbf7f3152bf66baba7d5e1ab61977e

Verification & scope

A deterministic bounded teaching model with stipulated toy conventions; not a production physics engine or spatial index. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:51:01.963419+00:00.

Case digest / d79d0aa2934f3163a8d513fba9febc680b9e41ba7a0116f69ecbf3accd8d2ecb