Cod sursa(job #443558)

Utilizator IlieeUngureanu Ilie Iliee Data 17 aprilie 2010 14:48:53
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include<cstdio>
#include<utility>
#include<vector>
#include<deque>
#define NV it->first
#define DV it->second
using namespace std;
vector<pair<int,int> > v[50010];
deque<int> q;
void read(),solve();
int n,m,A,B,C,L,D,N,cnt[50010],d[50010],oo=500000000,viz[50010],i;
int main()
{
	read();
	solve();
	return 0;
}
void read()
{
	freopen("bellmanford.in","r",stdin);
	freopen("bellmanford.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(;m;m--)
	{
		scanf("%d%d%d",&A,&B,&C);
		v[A].push_back(make_pair(B,C));
	}
}
void solve()
{
	vector<pair<int,int> >::iterator it;
	for(i=2;i<=n;i++)d[i]=oo;
	q.push_back(1);d[1]=0;
	for(;q.size();)
	{
		N=q.front();D=d[N];
		for(it=v[N].begin();it!=v[N].end();it++)
			if(D+DV<d[NV])
			{
				if(!viz[NV])
				{
					viz[NV]=1;cnt[NV]++;
					if(cnt[NV]>n)
					{
						printf("Ciclu negativ!\n");
						return;
					}
					q.push_back(NV);
				}
				d[NV]=D+DV;
			}
		q.pop_front(); viz[N]=0;
	}
	for(i=2;i<=n;i++)
		printf("%d ",d[i]); 
}