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#include <bits/stdc++.h>
#define INF 0x3f3f3f3f
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
struct edge {
int u, v, c;
edge() {}
edge(int _u, int _v, int _c) : u(_u), v(_v), c(_c) {}
};
struct Dinic {
int n, m = 0, s, t;
vector<edge> edges;
vector<vector<int>> g;
vector<int> q, level, ptr;
Dinic(int _n, int _m, int _s, int _t) : n(_n), s(_s), t(_t) {
edges.resize(2 * _m);
g.resize(n + 1);
q.resize(n + 1);
level.resize(n + 1);
ptr.resize(n + 1);
}
void addEdge(int u, int v, int c) {
g[u].emplace_back(m);
edges[m++] = {u, v, c};
g[v].emplace_back(m);
edges[m++] = {v, u, 0};
}
bool bfs() {
for (int i = 1; i <= n; ++i) {
level[i] = -1;
}
level[s] = 0;
int l = 0, r = -1;
q[++r] = s;
while (l <= r) {
int u = q[l++];
for (int id : g[u]) {
if (level[edges[id].v] == -1 && edges[id].c) {
level[edges[id].v] = level[u] + 1;
q[++r] = edges[id].v;
}
}
}
return level[t] != -1;
}
int dfs(int u, int flow) {
if (flow == 0) {
return 0;
}
if (u == t) {
return flow;
}
for (int &p = ptr[u]; p < (int)g[u].size(); ++p) {
int id = g[u][p];
int v = edges[id].v;
int c = edges[id].c;
if (level[v] != level[u] + 1 || c == 0) {
continue;
}
int minFlow = dfs(v, min(flow, c));
if (minFlow == 0) {
continue;
}
edges[id].c -= minFlow;
edges[id ^ 1].c += minFlow;
return minFlow;
}
return 0;
}
int maxFlow() {
int flow = 0;
while (bfs()) {
for (int i = 1; i <= n; ++i) {
ptr[i] = 0;
}
while (int newFlow = dfs(s, INF)) {
flow += newFlow;
}
}
return flow;
}
};
void testCase() {
int n, m;
fin >> n >> m;
Dinic g(n, m, 1, n);
for (int i = 0; i < m; ++i) {
int u, v, w;
fin >> u >> v >> w;
g.addEdge(u, v, w);
}
fout << g.maxFlow() << '\n';
}
int main() {
int tests = 1;
for (int tc = 0; tc < tests; ++tc) {
testCase();
}
fin.close();
fout.close();
return 0;
}