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#include <iostream>
#include <vector>
#include <queue>
#include <climits>
#include <cstring>

using namespace std;

int bfs(const vector<vector<long long>>& capacity, const vector<vector<int>>& adj, vector<int>& parent, int source, int sink) {
    fill(parent.begin(), parent.end(), -1);
    parent[source] = -2;  // Mark the source node
    queue<pair<int, long long>> q;
    q.push({source, LLONG_MAX});

    while (!q.empty()) {
        int cur = q.front().first;
        long long flow = q.front().second;
        q.pop();

        for (int next : adj[cur]) {
            if (parent[next] == -1 && capacity[cur][next] > 0) {
                parent[next] = cur;
                long long new_flow = min(flow, capacity[cur][next]);
                if (next == sink) {
                    return new_flow;
                }
                q.push({next, new_flow});
            }
        }
    }

    return 0;
}

long long fordFulkerson(int n, vector<vector<long long>>& capacity, const vector<vector<int>>& adj, int source, int sink) {
    long long max_flow = 0;
    vector<int> parent(n);

    long long new_flow;
    while ((new_flow = bfs(capacity, adj, parent, source, sink))) {
        max_flow += new_flow;
        int cur = sink;
        while (cur != source) {
            int prev = parent[cur];
            capacity[prev][cur] -= new_flow;
            capacity[cur][prev] += new_flow;
            cur = prev;
        }
    }

    return max_flow;
}

int main() {
    int n, m;
    cin >> n >> m;

    vector<vector<long long>> capacity(n, vector<long long>(n, 0));
    vector<vector<int>> adj(n);

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

    int source = 0;
    int sink = n - 1;

    cout << fordFulkerson(n, capacity, adj, source, sink) << endl;

    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: WRONG ANSWER

Test 12

Verdict: ACCEPTED