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input/code.cpp: In function 'int edmonds_karp(int, int, int)':
input/code.cpp:48:21: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   48 |     while (new_flow = bfs(source, sink, parent)) {
      |            ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

#include <iostream>
#include <vector>
#include <queue>
#include <climits>
#include <cstring>
using namespace std;
 
const int MAXN = 505;  // Maximum number of computers (nodes)
const int INF = INT_MAX;
 
int capacity[MAXN][MAXN];  // Capacity matrix for the graph
vector<int> adj[MAXN];     // Adjacency list for the graph
 
// Perform BFS to find an augmenting path, returns true if such a path exists
// and also stores the parent of each node in the path
int bfs(int source, int sink, vector<int>& parent) {
    fill(parent.begin(), parent.end(), -1);
    parent[source] = -2;  // Mark the source as visited
    queue<pair<int, int>> q;
    q.push({source, INF});  // (node, current flow)
 
    while (!q.empty()) {
        int cur = q.front().first;
        int flow = q.front().second;
        q.pop();
 
        for (int next : adj[cur]) {
            // If the next node is unvisited and the capacity from cur to next is non-zero
            if (parent[next] == -1 && capacity[cur][next] > 0) {
                parent[next] = cur;
                int new_flow = min(flow, capacity[cur][next]);
                if (next == sink) {
                    return new_flow;  // Found a path to the sink
                }
                q.push({next, new_flow});
            }
        }
    }
    return 0;  // No path found
}
 
// Edmonds-Karp algorithm to find maximum flow
int edmonds_karp(int source, int sink, int n) {
    int flow = 0;
    vector<int> parent(n + 1);
    int new_flow;
 
    while (new_flow = bfs(source, sink, parent)) {
        flow += new_flow;
        int cur = sink;
        while (cur != source) {
            int prev = parent[cur];
            capacity[prev][cur] -= new_flow;
            capacity[cur][prev] += new_flow;  // Add reverse flow
            cur = prev;
        }
    }
 
    return flow;
}
 
int main() {
    int n, m;
    cin >> n >> m;
 
    // Initialize the capacity matrix and adjacency list
    memset(capacity, 0, sizeof(capacity));
 
    for (int i = 0; i < m; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        capacity[a][b] += c;  // Handle multiple connections between the same pair of computers
        adj[a].push_back(b);
        adj[b].push_back(a);  // Add reverse edge for the residual graph
    }
 
    int maxFlow = edmonds_karp(1, n, n);
    cout << maxFlow << 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