Cod sursa(job #639942)

Utilizator R4DIC4LTeodorescu Oana Maria R4DIC4L Data 24 noiembrie 2011 13:37:45
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include<fstream>
#include<vector>
#include<queue>
#define inf 1000000000 
using namespace std;
vector <pair<int,int> > a[50001];
queue <int> q;
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
int i,j,m,n,viz[50001],x,y,c,k,d[50001];
int main ()
{
 f>>n>>m;
 for(i=1;i<=m;i++)
	{ 
	 f>>x>>y>>c;
     a[x].push_back(make_pair(y,c));
	}
 for(i=1;i<=n;i++)
	d[i]=inf;
 q.push(1);
 viz[1]=1;
 d[1]=0; 
 while(!(q.empty()))
	{
	 k=q.front();
	 
	 for(i=0;i<a[k].size();i++)
	    {
			int nod=a[k][i].first;
			int cost=a[k][i].second;
			y=d[k]+cost;
		 if(viz[nod]==0 || y<d[nod])
			{
			 q.push(nod);
			 d[nod]=y;
			 viz[nod]++;
			 if(viz[nod]>n)
				{ g<<"Ciclu negativ!";
			     return 0;
		        } 
			}
	    }
	 q.pop();
	}
 for(i=2;i<=n;i++)
	g<<d[i]<<" ";
 return 0;
}