Cod sursa(job #2261790)

Utilizator SenibelanMales Sebastian Senibelan Data 16 octombrie 2018 18:01:41
Problema Cuplaj maxim in graf bipartit Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <fstream>
#include <vector>
#include <cstring>
using namespace std;
ifstream fin("cuplaj.in");
ofstream fout("cuplaj.out");
const int NMax = 10000;
vector <int> G[NMax+5];
int R[NMax + 5], L[NMax + 5], Use[NMax + 5];
int N,M,E,Cuplaj,Ok;
void Read()
{
    fin >> N >> M >> E;
    for(int i = 1 ; i <= E; ++i)
    {
        int u,v;
        fin >> u >> v;
        G[u].push_back(v);
    }
}

int Pairup(int Nod)
{
    if(Use[Nod]) return 0;
    Use[Nod] = 1;
    for(auto Vecin : G[Nod])
    {
        if(!R[Vecin])
        {
            L[Nod] = Vecin;
            R[Vecin] = Nod;
            return 1;
        }
    }
    for(auto Vecin : G[Nod])
    {
        if(Pairup(R[Vecin]) == 1)
        {
            L[Nod] = Vecin;
            R[Vecin] = Nod;
            return 1;
        }
    }
    return 0;
}

void Print()
{
    for(int i = 1; i <= N; ++i)
        Cuplaj += (L[i]!=0);
    fout << Cuplaj << "\n";
    for(int i = 1; i <= N; ++i)
        if(L[i])
            fout << i << " "<< L[i] << "\n";
}

int main()
{
    Read();
    do
    {
    Ok = 0;
    memset(Use,0,sizeof(Use));
    for(int i = 1; i <= N; ++i)
        if(!L[i])
            Ok = Ok | Pairup(i);
    }
    while (Ok);

    Print();
    return 0;
}