Maximum stream dinic + sap Template

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Dinic + current arc optimization:

Struct edge {int X, Y, C, Ne;} e [M * 2]; int be [N], all; int d [N], Q [N]; int stack [N], top; // stack stores edge int cur [N]; // Current Arc Optimization
Void add (int x, int y, int Z) // you must ensure that the first side of the opposite side is an even number {e [all]. X = x; E [all]. y = y; E [all]. C = z; E [all]. ne = be [x]; Be [x] = All ++; E [all]. X = y; E [all]. y = x; E [all]. C = 0; E [all]. ne = be [y]; Be [y] = All ++ ;}
Bool BFS (int s, int t) // The hierarchy graph reduces the number of edges from m to N complexity. {memset (D,-1, sizeof (d )); int head = 0, tail = 0; Q [++ tail] = s; d [s] = 0; while (Head! = Tail) {int u = Q [++ head]; for (INT I = be [u]; I! =-1; I = E [I]. ne) if (E [I]. c> 0 & D [E [I]. y] =-1) {d [E [I]. y] = d [u] + 1; Q [++ tail] = E [I]. y; If (tail = N-1) tail = 0; If (E [I]. y = T) return 1 ;}} return 0 ;}int dinic (int s, int t) // use stack to simulate recursion. {int ans = 0; while (BFS (S, T) {memcpy (cur, Be, sizeof (be); int u = s; Top = 0; // DFS starts clearing the stack while (1) {If (u = T) {int minc = 1000000000, mini; For (INT I = 0; I <top; I ++) if (minc> E [stack [I]. c) {minc = E [stack [I]. c; Mini = I; // to return This continues to be extended} For (INT I = 0; I <top; I ++) {e [stack [I]. c-= minc; E [stack [I] ^ 1]. c + = minc; // The first binary is reversed to obtain the reverse edge.} ans + = minc; Top = mini; u = E [stack [mini]. X ;}for (INT I = cur [u]; I! =-1; cur [u] = I = E [cur [u]. ne) if (E [I]. c> 0 & D [E [I]. y] = d [E [I]. x] + 1) break; If (cur [u]! =-1) {stack [top ++] = cur [u]; u = E [cur [u]. y;} else {If (Top = 0) break; // The End mark of the loop D [u] =-1; // The current node does not delete u = E [stack [-- top] in the augmented path. x; // backtracking }}return ans ;}

ISAP + gap + current arc optimization:

Struct edge {int X, Y, C, Ne;} e [M * 2]; int X, Y, Z, n, m, S, T; int be [N], all; int d [N], Q [N]; int stack [N]; // simulate recursive int gap [N], cur [N]; // gap optimization + current arc optimization void add (int x, int y, int Z) // ensure that the first one is an even number {e [all]. X = x; E [all]. y = y; E [all]. C = z; E [all]. ne = be [x]; Be [x] = All ++; E [all]. X = y; E [all]. y = x; E [all]. C = 0; E [all]. ne = be [y]; Be [y] = All ++;} void BFS (int s, int t) {memset (D,-1, sizeof (d )); memset (GAP, 0, sizeof (GAP); Gap [0] = 1; int head = 0, Ta IL = 0; Q [++ tail] = T; d [T] = 0; while (Head! = Tail) {int u = Q [++ head]; for (INT I = be [u]; I! =-1; I = E [I]. ne) if (d [E [I]. y] =-1) {d [E [I]. y] = d [u] + 1; Q [++ tail] = E [I]. y; Gap [d [E [I]. y] ++ ;}}} int SAP (int s, int T, int N) {int ans = 0; BFS (S, T); memcpy (cur, be, sizeof (be); int Top = 0; int u = s; while (d [s] <n) {If (u = T) {int minc = 1000000000, mini; For (INT I = 0; I <top; I ++) if (minc> E [stack [I]. c) {minc = E [stack [I]. c; Mini = I ;}for (INT I = 0; I <top; I ++) {e [stack [I]. c-= minc; E [stack [I] ^ 1]. c + = minc;} ans + = Minc; Top = mini; u = E [stack [mini]. X; continue;} For (INT I = cur [u]; I! =-1; cur [u] = I = E [I]. ne) // Current Arc optimization if (E [I]. c> 0 & D [E [I]. y] + 1 = d [u]) break; If (cur [u]! =-1) {stack [top ++] = cur [u]; u = E [cur [u]. y;} else {int mind = N; For (INT I = be [u]; I! =-1; I = E [I]. ne) // update the distance label if (E [I]. c> 0 & mind> d [E [I]. y]) {mind = d [E [I]. y]; cur [u] = I;} gap [d [u] --; If (! Gap [d [u]) return ans; // gap indicates the number of points at the current distance. Once = 0, the fault exits directly. d [u] = mind + 1; gap [d [u] ++; If (u! = S) u = E [stack [-- top]. X ;}} return ans;} void Init () {All = 0; memset (be,-1, sizeof (be ));}