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#include <iostream>
#include <fstream>
#include <cstdlib>
#include <vector>
#include <queue>
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
#define ll long long
#define pb push_back
const int NMax = 1e3 + 5;
const ll inf = 1e9 + 5;
int N,M,nrSol;
bool vis[NMax];
int pre[NMax],cap[NMax][NMax];
vector<int> v[NMax];
bool bfs();
int main() {
in>>N>>M;
for (int i=1;i <= M;++i) {
int x,y,c;
in>>x>>y>>c;
if (!cap[x][y] && !cap[x][y]) {
v[x].pb(y);
v[y].pb(x);
}
cap[x][y] = c;
}
int maxFlow = 0;
while (bfs()) {
for (auto nxt : v[N]) {
if (!vis[nxt] || !cap[nxt][N]) {
continue;
}
int mnCap = inf, node = N;
pre[N] = nxt;
while (node != 1) {
mnCap = min(mnCap,cap[pre[node]][node]);
node = pre[node];
}
if (!mnCap) {
continue;
}
node = N;
while (node != 1) {
cap[pre[node]][node] -= mnCap;
cap[node][pre[node]] += mnCap;
node = pre[node];
}
maxFlow += mnCap;
}
}
out<<maxFlow<<'\n';
in.close();out.close();
return 0;
}
bool bfs() {
for (int i=1;i <= N;++i) {
vis[i] = false;
}
queue<int> Q;
Q.push(1);
bool reachedN = false;
while (Q.size()) {
int node = Q.front();
Q.pop();
if (node == N) {
reachedN = true;
continue;
}
for (auto nxt : v[node]) {
if (vis[nxt] || !cap[node][nxt]) {
continue;
}
vis[nxt] = true;
pre[nxt] = node;
Q.push(nxt);
}
}
return reachedN;
}