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Cod sursa(job #846229)
#include <stdio.h>
#include <vector>
using namespace std;
#define Max 50001
#define inf 0xffffff
vector<pair<int,int> >g[Max];
int n,m,d[Max],p[Max],nr;
struct heap{ int c,x; }h[Max];
void pop_heap()
{
h[1]=h[nr--];
p[h[1].x]=1;
int t,f;
t=1;f=2;
if(f+1<=nr && h[f+1].c<h[f].c)f++;
while(f<=nr && h[t].c < h[f].c)
{
swap(h[t],h[f]);
swap(p[h[t].x],p[h[f].x]);
t=f;f=2*t;
if(f+1<=nr && h[f+1].c<h[f].c)f++;
}
}
void push_heap(int x,int c)
{
int t,f;
if(p[x]==0)
{
nr++;
p[x]=nr;
h[nr].x=x;
h[nr].c=c;
f=nr;
} else
{
f=p[x];
h[f].c=c;
}
t=f/2;
while(t>0 && h[f].c < h[t].c)
{
swap(h[t],h[f]);
swap(p[h[t].x],p[h[f].x]);
f=t; t=f/2;
}
}
void dijkstra()
{
int x,y,c;
for(int i=2;i<=n;i++)d[i]=inf;
h[1].c=0;
h[1].x=1;
p[1]=1;
nr=1;
while(nr>0)
{
x=h[1].x;
c=h[1].c;
pop_heap();
for(int i=0;i<g[x].size();i++)
{
y=g[x][i].first;
if(d[y]>c+g[x][i].second)
{
d[y]=c+g[x][i].second;
push_heap(y,d[y]);
}
}
}
}
int main()
{
int x,y,c;
freopen("dijkstra.in","r",stdin);
freopen("dijkstra.out","w",stdout);
scanf("%d %d",&n,&m);
for(int i=1;i<=m;i++)
{
scanf("%d %d %d",&x,&y,&c);
g[x].push_back(make_pair(y,c));
}
dijkstra();
for(int i=2;i<=n;i++)printf("%d ",d[i]==inf?0:d[i]);
}