Cod sursa(job #2345832)

Utilizator rares1012Rares Cautis rares1012 Data 16 februarie 2019 18:46:15
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.42 kb
#include <bits/stdc++.h>
#define N 50000
#define Mxn 2000000000

std::queue<int> h;

std::vector< std::pair<int, int> > d[N];

int best[N];

int inq[N];

int prc[N];

void reset()
{
    for(int i=1; i<N; i++)
        best[i]=Mxn;
    best[0]=0;
    inq[0]=1;
}

int main()
{
    int n,m,i,a,b,c,x=1,nod,val,nod2,val2;
    FILE*fi,*fo;
    fi=fopen("bellmanford.in","r");
    fo=fopen("bellmanford.out","w");
    fscanf(fi,"%d%d",&n,&m);
    for(i=0; i<m; i++)
    {
        fscanf(fi,"%d%d%d",&a,&b,&c);
        a--;
        b--;
        d[a].push_back({b,c});
    }
    reset();
    h.push(0);
    while(h.empty()!=1 && x==1)
    {
        nod=h.front();
        val=best[nod];
        h.pop();
        inq[nod]=0;
        for(i=0; i<d[nod].size(); i++)
        {
            nod2=d[nod][i].first;
            val2=val+d[nod][i].second;
            if(best[nod2]>val2)
            {
                best[nod2]=val2;
                if(inq[nod2]==0)
                {
                    h.push(nod2);
                    inq[nod2]=1;
                }
                prc[nod2]++;
                if(prc[nod2]>=n)
                    x=0;
            }
        }
    }
    if(x==0)
        fprintf(fo,"Ciclu negativ!");
    else
    {
        for(i=1; i<n; i++)
        {
            fprintf(fo,"%d ",best[i]);
        }
    }
    fclose(fi);
    fclose(fo);
    return 0;
}