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FA-70751 / GIS polygon topology / Open access

Node degree classification in an arc-node topology: pseudo node degree · case 01

Four-way junctions are reported as pseudo-nodes.

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

ROOT CAUSE

Any even degree is labelled pseudo, including real four-way junctions.

VERIFIED REPAIR

At the pseudo node degree step restore `elif d == 2:`, leaving the rest of the model unchanged.

Unsuccessful approach: Degree 3 junctions are now labelled pseudo.

Case contract

Input [nodes, arcs] with integer node ids and arcs [arc_id, from, to]. Degree counts arc ends, so a loop adds 2 to its node. Label degree 0 "isolated", 1 "dangle", 2 "pseudo", 3 or more "node". Return [[node, degree, label], ...] in ascending numeric node order, including isolated nodes.

Why this case matters

Topology QA flags dangles (undershoots) and pseudo-nodes (unnecessary splits); miscounting loops turns valid island rings into errors.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    nodes, arcs = x
    deg = {n: 0 for n in nodes}
    for aid, u, v in arcs:
        deg[u] = deg.get(u, 0) + 1
        deg[v] = deg.get(v, 0) + 1
    out = []
    for n in sorted(deg):
        d = deg[n]
        if d == 0:
            label = 'isolated'
        elif d == 1:
            label = 'dangle'
        elif d % 2 == 0:
            label = 'pseudo'
        else:
            label = 'node'
        out.append([n, d, label])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']])], [('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #9', [[1, 2, 3, 4], [[1, 1, 2], [2, 2, 3], [3, 3, 1], [4, 1, 4], [5, 4, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']])], [('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #9', [[1, 2, 3, 4], [[1, 1, 2], [2, 2, 3], [3, 3, 1], [4, 1, 4], [5, 4, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])], [('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])], [('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])]]
for label, args, expected in fixtures[N-1]:
    check(label, 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 fixtureActualExpectedOutcome
control #0[[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']][[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]Passed
control #1[[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']][[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]Passed
regression #2[[7, 2, 'pseudo']][[7, 2, 'pseudo']]Passed
regression #3[[7, 3, 'node'], [8, 1, 'dangle']][[7, 3, 'node'], [8, 1, 'dangle']]Passed
control #4[[1, 4, 'pseudo'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']][[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]Failed
regression #5[[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']][[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]Passed
regression #6[[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']][[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]Passed
regression #7[[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']][[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]Passed

SHA-256 / 5ca682cccf6f4e83910d128cfa9bdfa488bc33faab99158c2900828bed4a7ac8

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    nodes, arcs = x
    deg = {n: 0 for n in nodes}
    for aid, u, v in arcs:
        deg[u] = deg.get(u, 0) + 1
        deg[v] = deg.get(v, 0) + 1
    out = []
    for n in sorted(deg):
        d = deg[n]
        if d == 0:
            label = 'isolated'
        elif d == 1:
            label = 'dangle'
        elif d <= 3:
            label = 'pseudo'
        else:
            label = 'node'
        out.append([n, d, label])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']])], [('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #9', [[1, 2, 3, 4], [[1, 1, 2], [2, 2, 3], [3, 3, 1], [4, 1, 4], [5, 4, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']])], [('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #9', [[1, 2, 3, 4], [[1, 1, 2], [2, 2, 3], [3, 3, 1], [4, 1, 4], [5, 4, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])], [('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])], [('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])]]
for label, args, expected in fixtures[N-1]:
    check(label, 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 fixtureActualExpectedOutcome
control #0[[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']][[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]Passed
control #1[[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']][[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]Passed
regression #2[[7, 2, 'pseudo']][[7, 2, 'pseudo']]Passed
regression #3[[7, 3, 'pseudo'], [8, 1, 'dangle']][[7, 3, 'node'], [8, 1, 'dangle']]Failed
control #4[[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']][[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]Passed
regression #5[[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']][[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]Passed
regression #6[[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']][[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]Passed
regression #7[[1, 3, 'pseudo'], [2, 3, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']][[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]Failed

SHA-256 / ac8aa5fbac4d0cd069c0af628a452de0b779b3df39322637981543592a98924f

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    nodes, arcs = x
    deg = {n: 0 for n in nodes}
    for aid, u, v in arcs:
        deg[u] = deg.get(u, 0) + 1
        deg[v] = deg.get(v, 0) + 1
    out = []
    for n in sorted(deg):
        d = deg[n]
        if d == 0:
            label = 'isolated'
        elif d == 1:
            label = 'dangle'
        elif d == 2:
            label = 'pseudo'
        else:
            label = 'node'
        out.append([n, d, label])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']])], [('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #9', [[1, 2, 3, 4], [[1, 1, 2], [2, 2, 3], [3, 3, 1], [4, 1, 4], [5, 4, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']])], [('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #9', [[1, 2, 3, 4], [[1, 1, 2], [2, 2, 3], [3, 3, 1], [4, 1, 4], [5, 4, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])], [('control #0', [[1, 2, 3, 4], [[10, 1, 2], [11, 2, 3], [12, 3, 4], [13, 4, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('control #1', [[1, 2, 3], [[10, 1, 2], [11, 2, 3]]], [[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]), ('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #10', [[12, 3, 25, 100], [[1, 3, 12], [2, 12, 25], [3, 25, 3], [4, 100, 3]]], [[3, 3, 'node'], [12, 2, 'pseudo'], [25, 2, 'pseudo'], [100, 1, 'dangle']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])], [('regression #2', [[7], [[30, 7, 7]]], [[7, 2, 'pseudo']]), ('regression #3', [[7, 8], [[30, 7, 7], [31, 7, 8]]], [[7, 3, 'node'], [8, 1, 'dangle']]), ('control #4', [[1, 2, 3, 4, 5], [[1, 1, 2], [2, 1, 3], [3, 1, 4], [4, 1, 5]]], [[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]), ('regression #5', [[2, 10, 11, 3], [[1, 2, 10], [2, 10, 11], [3, 11, 3], [4, 3, 2]]], [[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]), ('regression #6', [[1, 2, 9, 10], [[1, 1, 2], [2, 2, 10], [3, 10, 1]]], [[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]), ('regression #7', [[1, 2, 3, 4], [[1, 1, 2], [2, 1, 2], [3, 1, 2], [4, 3, 4], [5, 4, 3]]], [[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]), ('boundary #8', [[5], []], [[5, 0, 'isolated']]), ('control #11', [[1, 2, 3, 4, 5, 6], [[1, 1, 2], [2, 2, 3], [3, 3, 4], [4, 4, 5], [5, 5, 6], [6, 6, 1], [7, 1, 4]]], [[1, 3, 'node'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 3, 'node'], [5, 2, 'pseudo'], [6, 2, 'pseudo']])]]
for label, args, expected in fixtures[N-1]:
    check(label, 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 fixtureActualExpectedOutcome
control #0[[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']][[1, 2, 'pseudo'], [2, 2, 'pseudo'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]Passed
control #1[[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']][[1, 1, 'dangle'], [2, 2, 'pseudo'], [3, 1, 'dangle']]Passed
regression #2[[7, 2, 'pseudo']][[7, 2, 'pseudo']]Passed
regression #3[[7, 3, 'node'], [8, 1, 'dangle']][[7, 3, 'node'], [8, 1, 'dangle']]Passed
control #4[[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']][[1, 4, 'node'], [2, 1, 'dangle'], [3, 1, 'dangle'], [4, 1, 'dangle'], [5, 1, 'dangle']]Passed
regression #5[[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']][[2, 2, 'pseudo'], [3, 2, 'pseudo'], [10, 2, 'pseudo'], [11, 2, 'pseudo']]Passed
regression #6[[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']][[1, 2, 'pseudo'], [2, 2, 'pseudo'], [9, 0, 'isolated'], [10, 2, 'pseudo']]Passed
regression #7[[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']][[1, 3, 'node'], [2, 3, 'node'], [3, 2, 'pseudo'], [4, 2, 'pseudo']]Passed

SHA-256 / 1a38bec1be31087e7428ed97e96e36fca0d8b1612c53ef3c652f14da126a6058

Verification & scope

Stipulated deterministic toy contract on a bounded input domain; results are rounded as stated and no conformance with any published standard or library is claimed. 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 2026-09-29T14:48:23.584578+00:00.

Case digest / ee0dada36dd019af1728cc9e5880c2600cb0f691f980a5e0fca463109f76eba4