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Cod sursa(job #785561)
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
#define Max 50001
#define Inf 0xffffff
struct heap{ int x,d; } h[Max];
vector<pair<int,int> >g[Max];
int n,d[Max],pos[Max],k;
void add(int x,int d)
{
int t,f;
if( pos[x] == 0 )
{
k++;
h[k].x = x;
h[k].d = d;
pos[x] = k;
f = k;
} else
{
f = pos[x];
h[f].d = d;
}
t = f/2;
while(t > 0 && h[f].d < h[t].d)
{
swap(h[t],h[f]);
swap(pos[h[t].x],pos[h[f].x]);
f = t; t = f/2;
}
}
void remove()
{
int t,f;
pos[h[1].x] = 0;
h[1] = h[k--];
pos[h[1].x] = 1;
t = 1; f = 2;
if(f+1<=k && h[f+1].d < h[f].d)f++;
while(f <= k && h[f].d < h[t].d)
{
swap(h[t],h[f]);
swap(pos[h[t].x],pos[h[f].x]);
t = f; f = 2*t;
if(f+1<=k && h[f+1].d < h[f].d)f++;
}
}
void dijkstra()
{
int x,y;
for(int i=2;i<=n;i++)d[i] = Inf;
add(1,0);
while(k > 0)
{
x = h[1].x; remove();
for(int i=0;i<g[x].size();i++)
{
y = g[x][i].first;
if( d[y] > d[x] + g[x][i].second)
{
d[y] = d[x] +g[x][i].second;
add(y,d[y]);
}
}
}
}
int main()
{
int m,x,y,z;
freopen("dijkstra.in","r",stdin);
freopen("dijkstra.out","w",stdout);
scanf("%d %d",&n,&m);
while(m--)
{
scanf("%d %d %d",&x,&y,&z);
g[x].push_back(make_pair(y,z));
}
dijkstra();
for(int i=2;i<=n;i++)
if(d[i] == Inf)printf("0 "); else printf("%d ",d[i]);
return 0;
}