HDU 3549 Flow Problem (directed edge network Stream)

Question: n under T test data. m indicates n points. m points are directed to the weighted edge. m points are asked: how many test boards are tested from 1 to n maximum streams, I didn't have any idea. I used dinic below. I didn't consider reverse arc debug for a long time. I provided a large batch of test data.

# Include <iostream> # include <string> # include <cstring> # include <algorithm> # include <cstdio> # include <cctype> # include <queue> # include <stdlib. h> # include <cstdlib> # include <math. h> # include <set> # include <vector> # define inf 100000000 # define eps 1e-8 # define N 205 # define M 1050 # define ll intusing namespace std; inline ll Max (ll a, ll B) {return a> B? A: B;} inline ll Min (ll a, ll B) {return a <B? A: B;} // M indicates the number of edges. N indicates the number of points. 1-N // M indicates the number of edges. N indicates the number of points. from 1-nstruct Edge {int from, to, flow, cap, nex;} edge [M * 2]; // bidirectional edge. Note that the RE template combines the edge of the same starting vertex instead of the int head [N] And edgenum; // initialize two-1 and 0 void addedge (int u, int v, int cap) {// apply reverse arc Edge E = {u, v, 0, cap, head [u]}; edge [edgenum] = E; head [u] = edgenum ++; Edge E2 = {v, u, 0, 0, head [v]}; // if the cap is a unidirectional edge, it must be 0 edge [edgenum] = E2; head [v] = edgenum ++;} int dis [N], cur [N]; // The distance from the starting point. cur [I] indicates that the edge optimization being considered by the I point is not considered. The used vertex is initialized to hea. Dbool vis [N]; bool BFS (int Start, int End) {memset (vis, 0, sizeof (vis); memset (dis,-1, sizeof (dis); queue <int> Q; while (! Q. empty () Q. pop (); Q. push (Start); dis [Start] = 0; vis [Start] = 1; while (! Q. empty () {int u = Q. front (); Q. pop (); for (int I = head [u]; I! =-1; I = edge [I]. nex) {Edge E = edge [I]; if (! Vis [E. to] & E. cap> E. flow) {vis [E. to] = 1; dis [E. to] = dis [u] + 1; if (E. to = End) return true; Q. push (E. to) ;}}return false;} int DFS (int x, int a, int End) {// The inbound traffic to x is aif (x = End | a = 0) return a; int flow = 0, f; for (int & I = cur [x]; I! =-1; I = edge [I]. nex) {Edge & E = edge [I]; if (dis [x] + 1 = dis [E. to] & (f = DFS (E. to, Min (a, E. cap-E.flow), End)> 0) {E. flow + = f; edge [I ^ 1]. flow-= f; // flow + = f; a-= f; if (a = 0) break;} return flow ;} int Maxflow (int Start, int End) {int flow = 0; while (BFS (Start, End) {memcpy (cur, head, sizeof (head )); // copy the head array to flow + = DFS (Start, inf, End);} return flow;} int main () {int T, Cas = 1, n, m, I, a, B, c; scanf ("% d", & T); while (T --) {memset (head,-1, sizeof (head )); edgenum = 0; scanf ("% d", & n, & m); while (m --) {scanf ("% d", &, & B, & c); addedge (a, B, c);} printf ("Case % d: % d \ n", Cas ++, Maxflow (1, n);} return 0 ;} /* 993 21 2 12 3 13 31 2 12 3 11 3 13 21 3 21 3 53 21 2 4561 2 564313 3 3 1001 1 1001 1 10011 151 2 1 3 11 4 12 5 12 6 13 7 13 8 14 9 14 10 15 16 11 17 11 11 11 19 11 11 110 11 111 151 2 21 3 21 4 22 5 12 6 13 7 13 8 14 9 14 10 15 11 16 11 17 11 11 19 11 110 11 111 151 2 21 3 11 4 22 5 12 6 13 7 13 8 14 9 14 10 15 11 16 11 17 11 18 11 19 11 110 11 12 02 11 2 46514 41 2 102 1 52 4 201 3 34 51 2 102 1 52 4 201 3 33 4 19 101 5 22 4 62 3 4 1 2 93 9 55 9 42 3 14 2 16 7 13 24 41 2 101 3 23 4 12 4 14 41 2 11 3 13 4 102 4 10ans: 1270100365046511011722 */