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#include <bits/stdc++.h>
using namespace std;
#ifndef HOME
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
#else
ifstream fin("ciorna.in");
ofstream fout("ciorna.out");
#endif
using ll = long long;
class Flow {
const int max_flow = 1e9;
struct Edge { int from, to, cap; };
int n, k, s, t;
vector <Edge> e;
vector <vector <int>> g;
vector <int> lvl, rem;
public:
Flow(int n) : n(n), k(0), s(1), t(n), e(0), g(n + 1), lvl(n + 1, 0), rem(n + 1, 0) {}
void add_edge(int u, int v, int w) {
g[u].push_back(k++);
g[v].push_back(k++);
e.push_back({u, v, w});
e.push_back({v, u, 0});
}
inline bool bfs() {
fill(lvl.begin(), lvl.end(), 0);
queue <int> q;
for(lvl[s] = 1, q.push(s); !q.empty(); q.pop()) {
int u = q.front();
for(int id : g[u]) {
int v = e[id].to;
if(!lvl[v] && e[id].cap) {
lvl[v] = lvl[u] + 1;
q.push(v);
}
}
}
return lvl[t];
}
int dfs(int u, int flow) {
if(u == t || !flow) return flow;
for(int& cid = rem[u]; cid < g[u].size(); cid++) {
int id = g[u][cid], v = e[id].to;
if(!e[id].cap || lvl[v] != lvl[u] + 1) continue;
int f = dfs(v, min(flow, e[id].cap));
if(!f) continue;
e[id].cap -= f;
e[id ^ 1].cap += f;
return f;
}
return 0;
}
ll dinic(int ss, int tt) {
s = ss; t = tt;
ll flow = 0;
while(bfs()) {
fill(rem.begin(), rem.end(), 0);
while(int f = dfs(s, max_flow))
flow += f;
}
return flow;
}
};
int main()
{
int n, m, u, v, w;
fin >> n >> m;
Flow F(n);
for(int i = 1; i <= m; i++)
fin >> u >> v >> w,
F.add_edge(u, v, w);
fout << F.dinic(1, n);
return 0;
}