Cod sursa(job #2961745)

Utilizator TeoDiDiaconescu Teodora TeoDi Data 6 ianuarie 2023 22:08:14
Problema Cuplaj maxim in graf bipartit Scor 16
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.54 kb
#include <bits/stdc++.h>
#define oo 1e9

using namespace std;

//vector<vector<int> > cap;
//vector<vector<vector<int> > > muchie;
//vector<int> nivel;
int n, t;
int max_flow;

int MaxFlow(vector<vector<int>> &cap, int s, int t) {
    int n = cap.size();
    vector<vector<int>> flow(n, vector<int>(n));
    int ans = 0;
    while (true) {
        vector<int> par(n, -1);
        par[s] = -2;
        queue<int> q;
        q.push(s);
        while (!q.empty() && par[t] == -1) {
            int u = q.front();
            q.pop();
            for (int v = 0; v < n; v++) {
                if (par[v] == -1 && cap[u][v] - flow[u][v] > 0) {
                    par[v] = u;
                    q.push(v);
                }
            }
        }
        if (par[t] == -1) {
            break;
        }
        int f = INT_MAX;
        for (int v = t; v != s; v = par[v]) {
            f = min(f, cap[par[v]][v] - flow[par[v]][v]);
        }
        for (int v = t; v != s; v = par[v]) {
            flow[par[v]][v] += f;
            flow[v][par[v]] -= f;
        }
        ans += f;
    }
    return ans;
}
ifstream fin("cuplaj.in");
ofstream fout("cuplaj.out");

int main() {
    int n1, n2, m;
    fin >> n1 >> n2 >> m;
    n = n1 + n2 + 2;
    vector<vector<int>> cap(n, vector<int>(n));
    for(int i = 0; i < m; i++){
        int x, y, c;
        fin >> x >> y;
        cap[x][y + n1] = 1;
    }
    for(int i = 1; i <= n1; i++){
        cap[0][i] = 1;
    }
    for(int i = n1+1; i <= n1+n2; i++){
        cap[i][n-1] = 1;
    }
    fout<<MaxFlow(cap, 0, n-1);
    return 0;
}