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#include <bits/stdc++.h>
using namespace std;
struct Flow
{
int n;
struct Edge
{
int to;
int cap;
};
vector<Edge> edges;
vector<vector<int>> g;
vector<int> level;
vector<int> pt;
void init(int nn)
{
n = nn;
g.resize(n);
level.resize(n);
edges.clear();
pt.resize(n);
}
void addedge(int a, int b, int c)
{
a--;
b--;
assert(0 <= a && a < n);
assert(0 <= b && b < n);
edges.push_back({b, c});
edges.push_back({a, 0});
g[a].push_back((int) edges.size() - 2);
g[b].push_back((int) edges.size() - 1);
}
int dfs(int a, int cur)
{
if (cur == 0 || a == n - 1)
{
return cur;
}
for (int& eid = pt[a]; eid < (int) g[a].size(); eid++)
{
int i = g[a][eid];
if (level[edges[i].to] == 1 + level[a] && edges[i].cap)
{
int sol = dfs(edges[i].to, min(cur, edges[i].cap));
if (sol == 0)
{
continue;
}
edges[i].cap -= sol;
edges[i ^ 1].cap += sol;
return sol;
}
}
return 0;
}
int getflow()
{
int sol = 0;
while (1)
{
for (int i = 0; i < n; i++)
{
level[i] = -1;
pt[i] = 0;
}
level[0] = 0;
queue<int> q;
q.push(0);
while (!q.empty())
{
int a = q.front();
q.pop();
for (auto &i : g[a])
{
if (edges[i].cap && level[edges[i].to] == -1)
{
level[edges[i].to] = level[a] + 1;
q.push(edges[i].to);
}
}
}
if (level[n - 1] == -1)
{
break;
}
while (1)
{
int e = dfs(0, (int) 1e9);
if (e == 0)
{
break;
}
sol += e;
}
}
return sol;
}
};
signed main()
{
#ifdef ONPC
freopen ("input.txt", "r", stdin);
#endif // ONPC
#ifndef ONPC
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
freopen ("maxflow.in", "r", stdin);
freopen ("maxflow.out", "w", stdout);
#endif // ONPC
int n, m;
cin >> n >> m;
Flow g;
g.init(n);
for (int i = 1; i <= m; i++)
{
int a, b, c;
cin >> a >> b >> c;
g.addedge(a, b, c);
}
cout << g.getflow() << "\n";
}
/**
**/