Cod sursa(job #2868459)

Utilizator toda.emanuelatoda emanuela toda.emanuela Data 10 martie 2022 22:31:34
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.42 kb
#include <iostream>
#include <fstream>
#include <bitset>
#include <queue>
using namespace std;
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
int n,m,t[3][250001],start[50001],fr[50001],c[50001];
queue <int>q;
bitset <50001>viz;
bool ok=1;
void citire()
{
    int k=0,o,i,j,cost;
    f>>n>>m;
    for(o=1;o<=m;o++)
    {
        f>>i>>j>>cost;
        k++;
        t[0][k]=j;
        t[1][k]=start[i];
        t[2][k]=cost;
        start[i]=k;

    }
}

void initializare()
{
    int i;
    for(i=1;i<=n;i++)
        c[i]=1000001;
}
void ford(int nod)
{
    int p,x;
    c[1]=0;
    viz[nod]=1;
    q.push(nod);
    while(q.empty()==0)
    {
        x=q.front();
        p=start[x];
        viz[x]=0;
        fr[x]++;
        if(fr[x]>=n)
        {
            ok=0;
            return;
        }
        while(p)
        {
            if(c[x]+t[2][p]<c[t[0][p]])
            {
                c[t[0][p]]=c[x]+t[2][p];
                if(viz[t[0][p]]==0)
                {
                    viz[t[0][p]]=1;
                    q.push(t[0][p]);
                }
            }
            p=t[1][p];
        }
        q.pop();
    }

}
int main()
{
    citire();
    initializare();
    ford(1);
    if(ok==0)
    {
        g<<"Ciclu negativ!";
    }
    else
    {
        int i;
        for(i=2;i<=n;i++)
            g<<c[i]<<" ";
    }
    return 0;
}