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#include <cstdio>
#include <cstring>
#include <climits>
#include <vector>
#include <queue>
#include <algorithm>
const int MAX_N = 1000;
std::vector<int> neighbours[1 + MAX_N];
int cr[1 + MAX_N][1 + MAX_N];
bool visited[1 + MAX_N];
int from[1 + MAX_N];
bool bfs(int s, int d) {
memset(visited, 0, sizeof(visited));
std::queue<int> q;
q.push(s);
visited[s] = true;
from[s] = s;
while (!q.empty() && !visited[d]) {
int u = q.front();
q.pop();
for (auto v : neighbours[u]) {
if (!visited[v] && cr[u][v] > 0) {
q.push(v);
visited[v] = true;
from[v] = u;
}
}
}
return visited[d];
}
int maxFlow(int s, int d) {
int answer = 0;
while (bfs(s, d)) {
for (auto it : neighbours[d]) {
int flux = INT_MAX;
int u = it;
while (u != s) {
flux = std::min(flux, cr[from[u]][u]);
u = from[u];
}
u = it;
while (u != s) {
cr[from[u]][u] -= flux;
cr[u][from[u]] += flux;
u = from[u];
}
answer += flux;
}
}
return answer;
}
int main() {
freopen("maxflow.in", "r", stdin);
freopen("maxflow.out", "w", stdout);
int n, m;
scanf("%d%d", &n, &m);
for (int i = 0; i < m; i++) {
int u, v;
scanf("%d%d", &u, &v);
if (cr[u][v] == 0 && cr[v][u] == 0) {
neighbours[u].push_back(v);
neighbours[v].push_back(u);
}
scanf("%d", &cr[u][v]);
}
printf("%d\n", maxFlow(1, n));
return 0;
}