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Question 25913: Every Source-Side Vertex Subset Defines One Directed Cut Audit

On this page
  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

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R0050-25913 · q-20261015-advance-20261115-r05-max-flow-min-cut-theorem-0013

Original question and givens

Use complete directed vertices=[s, a0, a1, t], ordered edges=[[s, a0], [a0, t], [s, a1], [a1, t], [a0, s]], source=s, sink=t, aligned nonnegative exact capacities=[14, 14, 15, 15, 19]. A cut contains the source and excludes the sink; its capacity sums only edges leaving the cut, not incoming edges. Give (vertices, source, sink, cut_rows, cut_count, required_cut_count, certificate).

  • G001 — Use complete directed vertices=[s, a0, a1, t], ordered edges=[[s, a0], [a0, t], [s, a1], [a1, t], [a0, s]], source=s, sink=t, aligned nonnegative exact capacities=[14, 14, 15, 15, 19]. A cut contains the source and excludes the sink; its capacity sums only edges leaving the cut, not incoming edges. Give (vertices, source, sink, cut_rows, cut_count, required_cut_count, certificate).

Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.

Step-by-step derivation

S001 · implies

Before

source roles = [mfmc-complete-cut-enumeration]

After

derived = [[vertices, source, sink, cut_rows, cut_count, required_cut_count, certificate]]

Conditions: none

List the full source field order without JavaScript.LP weak uses13 fields,zero/strong15;premises and roles follow the original operation/mode without padding.

Step identifiers and dependencies

Rule: source_ordered_fields_without_JS · Uses: G001

S002 · implies

Before

source roles = [[s, a0, a1, t], [[s, a0], [a0, t], [s, a1], [a1, t], [a0, s]], [14, 14, 15, 15, 19], null, s, t]

After

derived = [[a0, a1, s, t], [[a0, s], [a0, t], [a1, t], [s, a0], [s, a1]], [19, 14, 15, 14, 15], null]

Conditions: none

Use2..12 vertices.Zip directed edges with capacity/flow by original index before sorting;reverse arcs remain distinct.Source and sink differ;reject loops/duplicates but allow zero capacities,no edges and isolated vertices.

Step identifiers and dependencies

Rule: MFMC_complete_directed_network_ZIP_before_source_order · Uses: G001, S001

S003 · calculation

Before

MFMC cut mask0 OUTWARD capacity := sum(14, 15)

After

MFMC cut mask0 OUTWARD capacity = 29

Conditions: none

Substitute original roles and established intermediates exactly,without floats;extra teaching identities do not impose new source numeric restrictions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · implies

Before

source roles = [0, [a0, a1], [s]]

After

derived = [[3, 4], [0], [[[s, a0], 14], [[s, a1], 15]], 29]

Conditions: none

S contains source and excludes sink.Enumerate every other-vertex subset;sort inside S by UTF16 but retain numeric-mask outer order.Capacity sums OUTWARD edges only,not incoming edges;ties are not re-sorted in English.

Step identifiers and dependencies

Rule: MFMC_EVERY_numeric_mask_cut_OUTWARD_edges_only · Uses: G001, S003

S005 · calculation

Before

MFMC cut mask1 OUTWARD capacity := sum(14, 15)

After

MFMC cut mask1 OUTWARD capacity = 29

Conditions: none

Substitute original roles and established intermediates exactly,without floats;extra teaching identities do not impose new source numeric restrictions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S004

S006 · implies

Before

source roles = [1, [a0, a1], [a0, s]]

After

derived = [[1, 4], [], [[[a0, t], 14], [[s, a1], 15]], 29]

Conditions: none

S contains source and excludes sink.Enumerate every other-vertex subset;sort inside S by UTF16 but retain numeric-mask outer order.Capacity sums OUTWARD edges only,not incoming edges;ties are not re-sorted in English.

Step identifiers and dependencies

Rule: MFMC_EVERY_numeric_mask_cut_OUTWARD_edges_only · Uses: G001, S005

S007 · calculation

Before

MFMC cut mask2 OUTWARD capacity := sum(15, 14)

After

MFMC cut mask2 OUTWARD capacity = 29

Conditions: none

Substitute original roles and established intermediates exactly,without floats;extra teaching identities do not impose new source numeric restrictions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S006

S008 · implies

Before

source roles = [2, [a0, a1], [a1, s]]

After

derived = [[2, 3], [0], [[[a1, t], 15], [[s, a0], 14]], 29]

Conditions: none

S contains source and excludes sink.Enumerate every other-vertex subset;sort inside S by UTF16 but retain numeric-mask outer order.Capacity sums OUTWARD edges only,not incoming edges;ties are not re-sorted in English.

Step identifiers and dependencies

Rule: MFMC_EVERY_numeric_mask_cut_OUTWARD_edges_only · Uses: G001, S007

S009 · calculation

Before

MFMC cut mask3 OUTWARD capacity := sum(14, 15)

After

MFMC cut mask3 OUTWARD capacity = 29

Conditions: none

Substitute original roles and established intermediates exactly,without floats;extra teaching identities do not impose new source numeric restrictions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · implies

Before

source roles = [3, [a0, a1], [a0, a1, s]]

After

derived = [[1, 2], [], [[[a0, t], 14], [[a1, t], 15]], 29]

Conditions: none

S contains source and excludes sink.Enumerate every other-vertex subset;sort inside S by UTF16 but retain numeric-mask outer order.Capacity sums OUTWARD edges only,not incoming edges;ties are not re-sorted in English.

Step identifiers and dependencies

Rule: MFMC_EVERY_numeric_mask_cut_OUTWARD_edges_only · Uses: G001, S009

S011 · implies

Before

source roles = [[a0, a1, s, t], [a0, a1]]

After

derived = [4, 4, 29, [[s], [a0, s], [a1, s], [a0, a1, s]]]

Conditions: none

Every s–t cut uniquely corresponds to a subset of other vertices,so all2^(n−2) cuts are compared.Select the minimum and all minimizers from this same complete family,retaining mask tie order.

Step identifiers and dependencies

Rule: MFMC_ALL_cut_family_complete_minimum_and_ALL_ties · Uses: G001, S010

Reverse checks

  • S011 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S010 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S009 · premise_and_result_audit — Recompute MFMC cut mask3 OUTWARD capacity with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S007 · premise_and_result_audit — Recompute MFMC cut mask2 OUTWARD capacity with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S005 · premise_and_result_audit — Recompute MFMC cut mask1 OUTWARD capacity with exact rational arithmetic, not rounded decimals.
  • S004 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S003 · premise_and_result_audit — Recompute MFMC cut mask0 OUTWARD capacity with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.

Result

([a0, a1, s, t], s, t, [[[s], [[[s, a0], 14], [[s, a1], 15]], 29], [[a0, s], [[[a0, t], 14], [[s, a1], 15]], 29], [[a1, s], [[[a1, t], 15], [[s, a0], 14]], 29], [[a0, a1, s], [[[a0, t], 14], [[a1, t], 15]], 29]], 4, 4, every_subset_containing_s_and_excluding_t_is_enumerated_and_only_forward_edges_are_counted)

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.

This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
  • input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
  • original question SHA-256: 112bc19f4fa4fc07fd314ed1e88462bd70a84649cb34571c0eeb45429c35fd4a
  • candidate record SHA-256: a71de6f03a996dd3df33fb0131946309abb1758c523f11d787a87c917cdce219
  • semantic review receipt SHA-256: 74c63a2c12285a3b2073f8d9f102bc2ba5fb7ed890c5b7c3b8afa94f032eda82
  • question-first witness SHA-256: 6d56428610f8e86c45fd00a2ad3b27ad9c052956946f0b91d71a68536f79d95f
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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