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#include <bits/stdc++.h>
using namespace std;

#define I_2D(row, col, width) ((row) * (width) + (col))
#define PRINT_ARR(arr, n)                                                      \
  do {                                                                         \
    for (int i = 0; i < n; i++) {                                              \
      cout << arr[i] << " ";                                                   \
    }                                                                          \
    cout << "\n";                                                              \
  } while (0)
#define PRINT_VEC_ARR(v, n)                                                    \
  do {                                                                         \
    for (int i = 0; i < n; i++) {                                              \
      cout << i << ": ";                                                       \
      for (auto item : v[i]) {                                                 \
        cout << item << " ";                                                   \
      }                                                                        \
      cout << endl;                                                            \
    }                                                                          \
  } while (0)
#define N 501

typedef long long ll;
ll w[N][N];
vector<ll> edges[N];

ll bfs(ll size, ll *p, ll last) {
  memset(p, 0, size * sizeof(ll));
  p[0] = -1;
  queue<pair<ll, ll>> q;
  q.push({1, LONG_LONG_MAX});
  ll curr, min_flow;
  while (!q.empty()) {
    curr = q.front().first - 1;
    min_flow = q.front().second;
    q.pop();

    for (auto n : edges[curr]) {
      if (!w[curr][n] || p[n]) {
        continue;
      }
      p[n] = curr + 1;
      if (n == last) {
        return min(min_flow, w[curr][n]);
      }
      q.push({n + 1, min(min_flow, w[curr][n])});
    }
  }
  return 0;
}

ll max_flow(ll n) {
  ll flow = 0;
  ll p[n];

  ll tmp, curr;
  while ((tmp = bfs(n, p, n - 1))) {
    curr = n - 1;
    flow += tmp;
    while (p[curr] != -1) {
      w[p[curr] - 1][curr] -= tmp;
      w[curr][p[curr] - 1] += tmp;

      curr = p[curr] - 1;
    }
  }

  return flow;
}

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int n, m;
  cin >> n >> m;

  ll a, b, c;
  for (int i = 0; i < m; i++) {
    cin >> a >> b >> c;
    a--;
    b--;
    edges[a].push_back(b);
    edges[b].push_back(a);
    w[a][b] += c;
  }

  cout << max_flow(n) << endl;
  return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED