Pagini recente » Cod sursa (job #1137475) | Cod sursa (job #1809711)
#include<cstdio>
#include<algorithm>
#include<vector>
#include<queue>
const int NMAX=50001,INF=2147483647;
std::vector<std::pair<int,int> > vecini[NMAX];
std::queue<int> coada;
int val[NMAX];
bool fol[NMAX];
void Init(int n)
{
for(int i=1;i<=n;i++)
val[i]=INF;
}
void Bellman_Ford(int n,int m)
{
coada.push(1);
val[1]=0;
int pas=0;
while(!coada.empty() && pas<=n*m)
{
pas++;
int x=coada.front();
coada.pop();
fol[x]=false;
for(std::vector<std::pair<int,int> >::iterator i=vecini[x].begin();i!=vecini[x].end();i++)
{
int a,b;
a=i->first; b=i->second;
if(val[x]+i->second<val[i->first])
{
val[i->first]=val[x]+i->second;
if(!fol[i->first])
{
coada.push(i->first);
fol[i->first]=true;
}
}
}
}
}
int main()
{
FILE *in=fopen("bellmanford.in","r");
int n,m;
fscanf(in,"%d %d ",&n,&m);
for(int i=1;i<=m;i++)
{
int x,y,cost;
fscanf(in,"%d %d %d ",&x,&y,&cost);
vecini[x].push_back(std::make_pair(y,cost));
}
fclose(in);
Init(n);
Bellman_Ford(n,m);
FILE *out=fopen("bellmanford.out","w");
for(int i=2;i<=n;i++)
{
fprintf(out,"%d ",val[i]);
}
fclose(out);
return 0;
}