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#include <iostream>
#include <queue>
#include <vector>
using namespace std;
const int INF = 1e9;
class Graph {
private:
    vector<vector<int>> adj_list;
public:
    Graph() {}
    Graph(int n) {
        adj_list.resize(n);
    }
    void add_edge(int a, int b) {
        adj_list[a].push_back(b);
    }
    vector<int> get_neighbours(int x) {
        return adj_list[x];
    }
    
};

class FordFulkerson {
private:
    int n;
    vector<vector<int>> capacity;
    Graph adj;
public:
    FordFulkerson(int n, vector<vector<int>> capacity, Graph adj) {
        this->n = n;
        this->capacity = capacity;
        this->adj = adj;
    }
    bool dfs(int S, int E, vector<bool> & visited, vector<int> & path) {
        visited[S] = true;
        path.push_back(S);
        
        if(S == E) {
            return true;
        }
        for(int neighbour : adj.get_neighbours(S)) {
            if(!visited[neighbour] and capacity[S][neighbour] > 0) {
                if(dfs(neighbour, E, visited, path)) {
                    return true;
                }
            }
        }
        path.pop_back();
        return false;
    }
    int ford_fulkerson(int S, int E) {
        int flow = 0;
        vector<bool> visited(n, false);
        vector<int> path;
        
        while(true) {
            int path_flow = INF;
            fill(visited.begin(), visited.end(), false);
            path.clear();
            if(!dfs(S, E, visited, path)) {
                break;
            }
            
            
            for(int i = 0; i < path.size() - 1; i++) {
                int a = path[i];
                int b = path[i + 1];
                path_flow = min(path_flow, capacity[a][b]);
            }
            for(int i = 0; i < path.size() - 1; i++) {
                int a = path[i];
                int b = path[i + 1];
                capacity[a][b] -= path_flow;
                capacity[b][a] += path_flow;
                
            }
            flow += path_flow;
        }
        
        return flow;
    }
};

int main() {
    int V = 6;
    int graph[6][6] = { {0, 16, 13, 0, 0, 0},
                           {0, 0, 10, 12, 0, 0},
                           {0, 4, 0, 0, 14, 0},
                           {0, 0, 9, 0, 0, 20},
                           {0, 0, 0, 7, 0, 4},
                           {0, 0, 0, 0, 0, 0}
                         };
    Graph adj(6);
    vector<vector<int>> capacity(6, vector<int>(6, 0));
    for(int i = 0; i < 6; i++) {
        for(int j = 0; j < 6; j++) {
            capacity[i][j] = graph[i][j];
            if(graph[i][j] != 0) {
                adj.add_edge(i, j);
            }
        }
    }
    FordFulkerson ff(6, capacity, adj);
    cout << ff.ford_fulkerson(0, 5) << endl;
    return 0;
}