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Cod sursa(job #767113)
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
#define MAX 50005
#define INF 0xfffffff
vector<pair<int,int> >g[MAX];
struct comp{ int c,x; }h[MAX];
int n,d[MAX],pos[MAX],nr;
void remove(){
pos[ h[1].x ] = 0;
h[1] = h[nr--];
int t = 1,f = 2;
if( nr > 2 && h[3].c < h[2].c )f++;
while( f <= nr && h[t].c > h[f].c )
{
swap( h[t],h[f] );
swap( pos[ h[t].x ],pos[ h[f].x ] );
t = f; f = 2*t;
if( f+1 <= nr && h[f+1].c < h[f].c )f++;
}
}
void update(int c,int x){
int t,f;
if( pos[x] == 0 )
{
nr++;
h[nr].c = c;
h[nr].x = x;
pos[x] = nr;
f = nr;
} else {
h[ pos[x] ].c = c;
f = pos[x];
}
t = f/2;
while( t > 0 && h[t].c > h[f].c )
{
swap( h[t],h[f] );
swap( pos[ h[t].x ],pos[ h[f].x ] );
f = t; t = f/2;
}
}
void dijkstra(){
int x,y;
for(int i=2;i<=n;i++) d[i] = INF;
nr = 1;
h[1].c = 0; h[1].x = 1;
while( nr > 0 )
{
x = h[1].x;
remove();
for(int i=0;i<g[x].size();i++)
{
y = g[x][i].second;
if( d[y] > d[x] + g[x][i].first )
{
d[y] = d[x] + g[x][i].first;
update(d[y],y);
}
}
}
}
int main(){
int m,x,y,c;
freopen("dijkstra.in","r",stdin);
freopen("dijkstra.out","w",stdout);
scanf("%d %d",&n,&m);
while(m--)
{
scanf("%d %d %d",&x,&y,&c);
g[x].push_back( make_pair(c,y) );
}
dijkstra();
for(int i=2;i<=n;i++)printf("%d ",d[i] == INF ? 0 : d[i]);
return 0;
}