Cod sursa(job #2761581)

Utilizator MateGMGozner Mate MateGM Data 2 iulie 2021 19:26:06
Problema Cuplaj maxim de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 3 kb
#include <fstream>
#include <vector>
#include <cstring>
#include <queue>
#include <iostream>

#define maxn 605
#define maxm 50005
#define inf (1LL<<31)-1
using namespace std;

ifstream be("cmcm.in");
ofstream ki("cmcm.out");


pair<int,int> aux[maxm+5];
int cap[maxn+5][maxn+5];
int c[maxn+5][maxn+5];
vector<int>adj[maxn+5];
int new_d[maxn+5],old_d[maxn+5],real_d[maxn+5], d[maxn+5],l[maxn+5],in[maxn+5];
queue<int>q;
int n,m,fin,lef,righ,s;
int cost,fl;
bool in_queue[maxn];
priority_queue<pair<int,int> >pq;

bool dijkstra()
{
    for(int i=1;i<=n;i++)
        d[i]=inf;

    d[s]=0;
    real_d[s]=0;

    //priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int>> >pq;
    pq.push({d[s],s});

    while(!pq.empty())
    {
        auto best=pq.top();
        int z=-best.first;
        int x=best.second;

        pq.pop();

        if(z!=d[x])continue;
        for(auto p :adj[x])
        {
            if(cap[x][p]){
                int new_d = d[x] + c[x][p] + old_d[x] - old_d[p];
                if (new_d < d[p])
                {

                    d[p] = new_d;
                    real_d[p] = real_d[x] + c[x][p];
                    l[p] = x;
                    //cout<<p<<endl;
                    pq.push({-d[p], p});
                }
            }
        }
    }
    for(int i=1;i<=n;i++)
        old_d[i]=real_d[i];
    if(d[fin]==inf)
        return false;
    int minim=inf;
    for(int i=fin;i!=s;i=l[i]){
        minim=min(minim,cap[l[i]][i]);
    }
    cost+=minim*real_d[fin];
    fl+=minim;
    for(int i=fin;i!=s;i=l[i])
    {

        cap[l[i]][i]-=minim;
        cap[i][l[i]]+=minim;
    }

    return true;

}


bool bellmanford()
{
    //memset(old_d,0x3f,sizeof(old_d));
    for(int i=1;i<=n;i++)
        old_d[i]=inf;
    old_d[s]=0;
    for(q.push(s),in[s]=1;!q.empty();q.pop())
    {
        int i=q.front();
        in_queue[i]=false;
        for(auto p:adj[i])
        {
            if(cap[i][p])
            {
                if(old_d[i]+c[i][p]>=old_d[p])
                    continue;
                old_d[p]=old_d[i]+c[i][p];
                if(in_queue[p])
                    continue;
                in_queue[p]=true;
                q.push(p);

            }
        }
    }
    if(old_d[fin]==inf)
        return false;
    return true;

}



int main()
{
    be>>lef>>righ>>m;
    n=lef+righ+2;
    s=n-1,fin=n;
    for(int i=1;i<=m;i++)
    {
        int x,y,z;
        be>>x>>y>>z;
        y+=lef;
        cap[x][y]=1;
        c[x][y]=z;
        c[y][x]=-z;
        adj[x].push_back(y);
        adj[y].push_back(x);
        aux[i]={x,y};
    }
    for(int i=1;i<=lef;i++)
    {
        cap[s][i]=1;
        adj[s].push_back(i);
        adj[i].push_back(s);
    }
    for(int i=1;i<=righ;i++)
    {
        cap[lef+i][fin]=1;
        adj[fin].push_back(lef+i);
        adj[i+lef].push_back(fin);
    }

    bellmanford();
    while(dijkstra());
    ki<<fl<<" "<<cost<<"\n";
    for(int i=1;i<=m;i++)
    {
        if(cap[aux[i].first][aux[i].second]==0)
            ki<<i<<" ";
    }

    return 0;
}