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Cod sursa(job #285054)
#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
const int maxn = 1001;
#define pb push_back
#define inf 0x3f3f3f3f
int n, m;
int f[maxn][maxn], c[maxn][maxn];
vector<int> g[maxn];
int maxflow = 0;
int p[maxn], viz[maxn];
void read()
{
scanf("%d%d", &n, &m);
for (int i = 0; i < m; ++i)
{
int x, y, cc;
scanf("%d%d%d", &x, &y, &cc);
g[x].pb(y); g[y].pb(x);
c[x][y] += cc;
}
}
int bfs()
{
memset(viz, 0, sizeof(viz));
queue<int> Q;
Q.push(1);
viz[1] = 1;
while (!Q.empty())
{
int now = Q.front();
Q.pop();
for (int i = 0; i < g[now].size(); ++i)
{
int next = g[now][i];
if (viz[next]) continue;
if (c[now][next] - f[now][next] == 0) continue;
viz[next] = 1;
p[next] = now;
Q.push(next);
//if (next == n) return 1;
}
}
return viz[n];
}
/*
void flux()
{
while(bfs())
{
int minn = inf;
for (int i = n; i != 1; i = p[i])
minn = min(minn, c[p[i]][i] - f[p[i]][i]);
for (int i = n; i != 1; i = p[i])
{
f[p[i]][i] += minn;
f[i][p[i]] -= minn;
}
maxflow += minn;
}
}
*/
void flux()
{
while (bfs())
for (int i = 0; i < g[n].size(); ++i)
{
int akt = g[n][i];
if (f[akt][n] == c[akt][n] || !viz[akt]) continue;
p[n] = akt;
int minn = inf;
for (int j = n; j != 1; j = p[j])
minn = min(minn, c[p[j]][j] - f[p[j]][j]);
for (int j = n; j != 1; j = p[j])
{
f[p[j]][j] += minn;
f[j][p[j]] -= minn;
}
maxflow += minn;
}
}
int main()
{
freopen("maxflow.in","r",stdin);
freopen("maxflow.out","w",stdout);
read();
flux();
printf("%d\n", maxflow);
return 0;
}