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#include <bits/stdc++.h>
using namespace std;
#ifndef LOCAL
ifstream in("maxflow.in");
ofstream out("maxflow.out");
#define cin in
#define cout out
#endif //LOCAL
struct Edge
{
int u, v;
long long cap, flow;
Edge(int _u, int _v, int _cap)
{
u = _u; v = _v;
cap = _cap;
flow = 0;
}
};
struct Dinic {
const long long flow_inf = 1e18;
vector<Edge> edges;
vector<vector<int>> adj;
int n, m = 0;
int s, t;
vector<int> level, ptr;
queue<int> q;
Dinic(int _n, int _s, int _t)
{
n = _n; s = _s; t = _t;
adj.resize(n + 7);
level.resize(n + 7);
ptr.resize(n + 7);
}
void addEdge(int u, int v, long long cap)
{
edges.push_back(Edge(u, v, cap));
edges.push_back(Edge(v, u, 0));
adj[u].push_back(m);
adj[v].push_back(m + 1);
m += 2;
}
bool bfs()
{
while(!q.empty())
{
int u = q.front();
q.pop();
for(int id : adj[u])
{
if(edges[id].cap - edges[id].flow < 1)
continue;
if(level[edges[id].v] != -1)
continue;
level[edges[id].v] = level[u] + 1;
q.push(edges[id].v);
}
}
return level[t] != -1;
}
long long dfs(int u, long long pushed)
{
if(pushed == 0)
return 0;
if(u == t)
return pushed;
for(int& cid = ptr[u]; cid < adj[u].size(); ++cid)
{
int id = adj[u][cid];
int v = edges[id].v;
if(level[u] + 1 != level[v] || edges[id].cap - edges[id].flow < 1)
continue;
long long tr = dfs(v, min(pushed, edges[id].cap - edges[id].flow));
if(tr == 0)
continue;
edges[id].flow += tr;
edges[id ^ 1].flow -= tr;
return tr;
}
return 0;
}
long long flow()
{
long long f = 0;
while(true)
{
fill(level.begin(), level.end(), - 1);
level[s] = 0;
q.push(s);
if(!bfs())
break;
fill(ptr.begin(), ptr.end(), 0);
while(long long pushed = dfs(s, flow_inf)) {
f += pushed;
}
}
return f;
}
};
int main()
{
int n, m;
cin >> n >> m;
Dinic solver(n + 1, 1, n);
for(int i = 0; i < m; i++)
{
int x, y, c;
cin >> x >> y >> c;
solver.addEdge(x, y, c);
}
cout << solver.flow() << endl;
}