Cod sursa(job #862542)

Utilizator andonemadalin andone Data 22 ianuarie 2013 19:22:07
Problema Algoritmul Bellman-Ford Scor 15
Compilator cpp Status done
Runda Arhiva educationala Marime 1.06 kb
#include <fstream>
#define INF 1000000000
using namespace std; 
ifstream intrare("bellmanford.in");
ofstream iesire("bellmanford.out"); 
int n,start,nr,schimb,cmin[50001],Cost[5000][5000];
int coada[50001],p,u; 
int main()
{
    int i,m,x,y,cost,j,p,u;
    intrare>>n>>m;
	start=1;
    for(i=1;i<=n;i++)
        for(j=1;j<=n;j++)
            if(i!=j)
                Cost[i][j]=INF;
    for(i=1;i<=m;i++)
    {
        intrare>>x>>y>>cost;
        Cost[x][y]=cost;
    }
	for(i=1;i<=n;i++)
        cmin[i]=INF;
	//algoritm
    cmin[start]=0;
    u=1; p=1;
    coada[1]=start; x=start;
    while(p<=u)
    {
        x=coada[p++];
		schimb=0;
        for(i=1;i<=n;i++)
        {
            nr++;
            if(cmin[i]>cmin[x]+Cost[x][i]&&Cost[x][i]!=INF)
            {
                coada[++u]=i;
                cmin[i]=cmin[x]+Cost[x][i];
				schimb=1;
            }
        }
    }
    if(schimb)
		iesire<<"Ciclu negativ!"<<'\n';
    else
        for(i=2;i<=n;i++)
            iesire<<cmin[i]<<" ";
	iesire.close();
    return 0;
}