Cod sursa(job #448380)

Utilizator funkydvdIancu David Traian funkydvd Data 3 mai 2010 17:34:22
Problema Flux maxim Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.35 kb
#include <stdio.h>
#include <vector>
using namespace std;
#define NMAX 1024
#define pb push_back
#define sz size()
#define mp make_pair
#define INF 0x3f3f3f3f
int C[NMAX][NMAX],F[NMAX][NMAX],TT[NMAX],N, M,cd[NMAX],viz[NMAX];
vector<int> G[NMAX];
int BF()
{
	int i, j, nod, V;
	cd[0] = 1,cd[1] = 1;
	memset(viz, 0, sizeof(viz));
	viz[1] = 1;
	for (i = 1; i <= cd[0]; i++)
	{
		nod = cd[i];
                if (nod == N) continue;
		for (j = 0; j < G[nod].sz; j++) 
			{
				V = G[nod][j];
				if (C[nod][V] == F[nod][V] || viz[V]) continue;
				viz[V] = 1;
				cd[ ++cd[0] ] = V;
				TT[V] = nod;
			}
	}
	return viz[N];
}
int main()
{
	freopen("maxflow.in", "r", stdin);
	freopen("maxflow.out", "w", stdout);
	int i, flow, fmin, x, y, z, nod;
	scanf("%d %d ", &N, &M);
	for (i = 1; i <= M; i++)
	{
		scanf("%d %d %d ", &x, &y, &z);
		C[x][y] += z;
		G[x].pb(y),G[y].pb(x);
	}
	for (flow = 0; BF();)
		for (i = 0; i < G[N].sz; i++)
		{
			nod = G[N][i];
			if (F[nod][N] == C[nod][N] || !viz[nod]) continue;
			TT[N] = nod;
			fmin = INF;
			for (nod = N; nod != 1; nod = TT[nod]) 
				fmin = min(fmin, C[ TT[nod] ][nod] - F[ TT[nod] ][nod]);
			if (fmin == 0) continue;
			for (nod = N; nod != 1; nod = TT[nod])
				F[ TT[nod] ][nod] += fmin,F[nod][ TT[nod] ] -= fmin;
			flow += fmin;
		}
	printf("%d ", flow);
	return 0;
}