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#include <bits/stdc++.h>
using namespace std;
const int INF = (int) 1e9;
struct flow
{
int n;
vector<pair<int, int>> edges;
vector<vector<int>> g;
vector<int> level;
vector<int> pos;
flow(int nn)
{
n = nn;
pos.resize(n + 1);
level.resize(n + 1);
g.resize(n + 1);
edges.clear();
}
void add(int a, int b, int c)
{
g[a].push_back((int) edges.size());
g[b].push_back((int) edges.size() + 1);
edges.push_back({b, c});
edges.push_back({a, 0});
}
int dfs(int a, int pre)
{
if (a == n || pre == 0)
{
return pre;
}
while (pos[a] < (int) g[a].size())
{
int i = g[a][pos[a]];
int b = edges[i].first;
int c = edges[i].second;
pos[a]++;
if (c == 0 || level[b] != level[a] + 1)
{
continue;
}
int total = dfs(b, min(pre, c));
if (total)
{
edges[i].second -= total;
edges[i ^ 1].second += total;
return total;
}
}
return 0;
}
int get()
{
int sol = 0;
while (1)
{
for (int i = 1; i <= n; i++)
{
level[i] = -1;
pos[i] = 0;
}
level[1] = 0;
queue<int> q;
q.push(1);
while (!q.empty())
{
int a = q.front();
q.pop();
for (auto &i : g[a])
{
int b = edges[i].first;
int c = edges[i].second;
if (c && level[b] == -1)
{
level[b] = 1 + level[a];
q.push(b);
}
}
}
if (level[n] == -1)
{
break;
}
sol += dfs(1, INF);
}
return sol;
}
};
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
freopen ("maxflow.in", "r", stdin);
freopen ("maxflow.out", "w", stdout);
int n, m;
cin >> n >> m;
flow f(n);
for (int i = 1; i <= m; i++)
{
int a, b, c;
cin >> a >> b >> c;
f.add(a, b, c);
}
cout << f.get() << "\n";
}