Pagini recente » Cod sursa (job #627446) | Cod sursa (job #2522275) | Cod sursa (job #1193322) | Cod sursa (job #2614555) | Cod sursa (job #2505793)
#include <fstream>
#include <queue>
#include <vector>
using namespace std;
ifstream f("bellmanford.in"); ofstream g("bellmanford.out");
const int INF=1e9;
queue <int> q;
vector <pair<int,int>> G[50005];
int n,m,x,y,c,i,d[50005],nr[50005];
bool viz[50005];
bool Bellmanford()
{ bool ciclu=false;
while(!q.empty() && !ciclu)
{ x=q.front();
q.pop();
viz[x]=false;
for(int i=0;i<G[x].size();i++)
{ if(nr[G[x][i].second]>n) ciclu=true;
if(d[x]+G[x][i].first<d[G[x][i].second])
{ d[G[x][i].second]=d[x]+G[x][i].first;
if(!viz[G[x][i].second])
{ q.push(G[x][i].second);
viz[G[x][i].second]=true;
}
nr[G[x][i].second]=nr[x]+1;
if(nr[G[x][i].second]>n) ciclu=true;
}
}
}
return ciclu;
}
int main()
{ f>>n>>m;
for(i=1; i<=m; ++i)
{ f>>x>>y>>c;
G[x].push_back({c,y});
}
for(int i=1; i<=n; i++) d[i]=INF;
viz[1]=true; nr[1]=1;
q.push(1); d[1]=0;
if(Bellmanford())
g<<"Ciclu negativ!"<<'\n';
else
for(i=2; i<=n; i++)
g<<d[i]<<' ';
return 0;
}