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

// debug
template<class T> ostream& operator<<(ostream&, const vector<T>&);
template<class T> ostream& operator<<(ostream&, const set<T>&);
template<class T> ostream& operator<<(ostream&, const multiset<T>&);
template<class K, class V> ostream& operator<<(ostream&, const map<K, V>&);
template<class T, size_t N> ostream& operator<<(ostream&, const array<T, N>&);
template<class A, class B> ostream& operator<<(ostream& os, const pair<A, B>& p) { return os << "(" << p.first << ", " << p.second << ")"; }
template<class T>
void print_collection(ostream& os, const T& v) {
    os << "{";
    bool first = true;
    for (const auto& x : v) {
        if (!first) os << ", ";
        first = false;
        os << x;
    }
    os << "}";
}
template<class T> ostream& operator<<(ostream& os, const vector<T>& v) { print_collection(os, v); return os; }
template<class T> ostream& operator<<(ostream& os, const set<T>& v) { print_collection(os, v); return os; }
template<class T> ostream& operator<<(ostream& os, const multiset<T>& v) { print_collection(os, v); return os; }
template<class K, class V> ostream& operator<<(ostream& os, const map<K, V>& v) { print_collection(os, v); return os; }
template<class T, size_t N> ostream& operator<<(ostream& os, const array<T, N>& v) { print_collection(os, v); return os; }
#define dbg(x) cerr << #x << " = " << (x) << '\n'

using ll = long long;
constexpr int INF = 1'000'000'000; // 1e9
constexpr ll LINF = 1'000'000'000'000'000'000LL; // 1e18
constexpr int MOD = 1'000'000'007; // 1e9 + 7

inline ll add(ll a, ll b) { return (a + b) % MOD; }
inline ll sub(ll a, ll b) { return ((a - b) % MOD + MOD) % MOD; }
inline ll mul(ll a, ll b) { return (a * b) % MOD; }


void solve() {
    int N, M;
    cin >> N >> M;

    vector<vector<int>> adj(N + 1);
    vector<vector<ll>> cap(N + 1, vector<ll>(N + 1, 0));

    ll maxCap = 0;
    for (int i = 0; i < M; i++) {
        int a, b;
        ll c;
        cin >> a >> b >> c;

        adj[a].push_back(b);
        adj[b].push_back(a);

        cap[a][b] += c;
        maxCap = max(maxCap, cap[a][b]);
    }

    ll threshold = 1;
    while (threshold <= maxCap / 2) {
        threshold *= 2;
    }

    vector<char> visited(N + 1, 0);

    auto dfs = [&](auto&& dfs, int u, ll pushed, ll threshold) -> ll {
        if (u == N) return pushed;

        visited[u] = 1;

        for (int v : adj[u]) {
            if (visited[v] || cap[u][v] < threshold) continue;

            ll f = dfs(dfs, v, min(pushed, cap[u][v]), threshold);

            if (f > 0) {
                cap[u][v] -= f;
                cap[v][u] += f;
                return f;
            }
        }

        return 0;
    };

    ll flow = 0;
    for (; threshold > 0; threshold /= 2) {
        while (true) {
            fill(visited.begin(), visited.end(), 0);

            ll pushed = dfs(dfs, 1, LINF, threshold);

            if (pushed == 0) break;

            flow += pushed;
        }
    }

    cout << flow << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    solve();

    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