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#include <bits/stdc++.h>
using namespace std;
/// by iterating all neighbours of the sink
const int DIM_MAX = 1010;
namespace Flow {
int tata[DIM_MAX];
int c[DIM_MAX][DIM_MAX];
vector <int> adia[DIM_MAX];
int s, d;
bool bfs() {
memset(tata, 0, sizeof tata);
queue <int> q;
q.push(s);
tata[s] = -1;
while (!q.empty()) {
int nod = q.front();
q.pop();
for (auto i : adia[nod]) {
if (c[nod][i] && !tata[i]) {
tata[i] = nod;
q.push(i);
}
}
}
return tata[d];
}
int augment() {
int add = 1e9;
for (int i = d; i != s; i = tata[i])
add = min(add, c[tata[i]][i]);
for (int i = d; i != s; i = tata[i])
c[tata[i]][i] -= add, c[i][tata[i]] += add;
assert(add != 0);
return add;
}
int max_flow(int _s, int _d, int n) {
s = _s, d = _d;
int flow = 0;
while (bfs()) {
for (int i = 1; i <= n; i++) {
if (c[i][d]) {
assert(i != d);
tata[d] = i;
flow += augment();
}
}
}
return flow;
}
}
int main()
{
ifstream in("maxflow.in");
ofstream out("maxflow.out");
int n, m, a, b, c;
in >> n >> m;
while (m--) {
in >> a >> b >> c;
Flow::c[a][b] += c;
Flow::adia[a].push_back(b);
Flow::adia[b].push_back(a);
}
out << Flow::max_flow(1, n, n) << '\n';
return 0;
}