Cod sursa(job #1003458)

Utilizator Kira96Denis Mita Kira96 Data 30 septembrie 2013 19:24:44
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.88 kb
#include<fstream>
#include<queue>
#include<vector>
#define inf 1<<30
#define N 51000
using namespace std;
ifstream f("bellmanford.in");
ofstream g("bellmanford.out");
vector<pair<int,int> > v[N];
int qu[N],viz[N],D[N],i,nod,des,cos,x,y,c,m,n;
queue<int> q;
int bellmanford()
{
	q.push(1); viz[1]=qu[1]=1;
	while(!q.empty())
	{
		nod=q.front();
		q.pop();
		qu[nod]=0;
		for(i=0;i<v[nod].size();++i)
		{
			des=v[nod][i].first;
			cos=v[nod][i].second;
			if(D[nod]+cos<D[des])
			{
				D[des]=D[nod]+cos;
				if(!qu[nod])
					qu[nod]=1;
				if(++viz[des]>n)
					return 1;
				q.push(des);
			}
		}
	}
	return 0;
}
int main ()
{
	f>>n>>m;
	for(i=1;i<=m;++i)
	{
		f>>x>>y>>c;
		v[x].push_back(make_pair(y,c));
	}
	for(i=2;i<=n;++i)
		D[i]=inf;
	if(bellmanford())
		g<<"Ciclu negativ!";
	else
	{
		for(i=2;i<=n;++i)
			g<<D[i]<<" ";
	}
	return 0;
}