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#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <fstream>
#include <limits.h>
#include <math.h>
#include <queue>
#include <set>
#include <array>
#include <bitset>
using namespace std;
int cap[1005][1005];
int flow[1005][1005];
int prv[1005];
vector<int> G[1005];
bitset<1005> used;
bool bfs(int source, int sink) {
queue<int> Q;
used.reset();
Q.push(source);
used[source] = 1;
while (!Q.empty()) {
int nod = Q.front();
Q.pop();
if (nod == sink) continue;
for (auto& dest: G[nod]) {
if (used[dest] || flow[nod][dest] == cap[nod][dest]) continue;
Q.push(dest);
prv[dest] = nod;
used[dest] = 1;
}
}
return used[sink];
}
int edmond_karp(int source, int sink) {
int res = 0;
const int INF = int(2e9);
while (bfs(source, sink)) {
for (auto& neigh: G[sink]) {
if (flow[neigh][sink] == cap[neigh][sink] || !used[neigh]) continue;
int minFlow = INF;
prv[sink] = neigh;
for (int i = sink; i != source; i = prv[i]) {
minFlow = min(minFlow, cap[prv[i]][i] - flow[prv[i]][i]);
}
if (minFlow == 0) continue;
for (int i = sink; i != source; i = prv[i]) {
flow[prv[i]][i] += minFlow;
flow[i][prv[i]] -= minFlow;
}
res += minFlow;
}
}
return res;
}
int main() {
ios::sync_with_stdio(false);
string filename = "maxflow";
ifstream cin(filename + ".in");
ofstream cout(filename + ".out");
int n, m;
cin >> n >> m;
while (m--) {
int a, b, c;
cin >> a >> b >> c;
G[a].push_back(b);
G[b].push_back(a);
cap[a][b] = c;
}
cout << edmond_karp(1, n);
//system("pause");
return 0;
}