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#include <fstream>
#include <algorithm>
#include <vector>
using namespace std;
#define Nmax 50001
#define pb push_back
#define inf 1001
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
int n,m,i,a,b,x,w;
int H[Nmax],h,poz[Nmax],d[Nmax];
vector<int> v[Nmax],c[Nmax];
void afis()
{
g<<"d: ";for(i=2;i<=n;i++) if(d[i]==inf) g<<"inf "; else g<<d[i]<<" "; g<<"\n";
g<<"poz: ";for(i=2;i<=n;i++) if(poz[i]==-1) g<<"0 "; else g<<poz[i]<<" "; g<<"\n";
g<<"H: ";for(i=1;i<=h;i++) g<<H[i]<<" "; g<<"\n";
g<<"d[H]: ";for(i=1;i<=h;i++) g<<d[H[i]]<<" "; g<<"\n";
g<<"\n";
}
void perc(int x)
{
int xx;
while(x>1)
{
xx=x/2;
if (d[H[xx]]>d[H[x]])
{
poz[H[x]]=xx;
poz[H[xx]]=x;
swap(H[x],H[xx]);
x=xx;
}
else x=1;
}
}
void sift(int x)
{
int son,xx,xy;
while(x<=h)
{
xx=x*2;
xy=xx+1;
if (xx<=h)
{
son=xx;
if(xy<=h)
if(d[H[xy]]<d[H[xx]]) son=xy;
}
else return;
if (d[H[x]]>d[H[son]])
{
poz[H[x]]=son;
poz[H[son]]=x;
swap(H[x],H[son]);
x=son;
}
else return;
}
}
void dijkstra_heap()
{
//initializare
int j,q;
for(j=2;j<=n;j++) {d[j]=inf; poz[j]=-1;}
poz[1]=1;
H[++h]=1;
while(h)
{
//eliminam minimul
int minim=H[1];
swap(H[1],H[h]);
poz[H[1]]=1;
--h;
sift(1);
w=v[minim].size();
g<<"\n~~~~~~~~~~~~~\n";
afis();
g<<"---------------\n";
for(q=0;q<w;q++)
{
/*g<<"d[v[minim][q]]=d["<<v[minim][q]<<"]="<<d[v[minim][q]]<<"\n";
g<<"d[minim]=d["<<minim<<"]="<<d[minim]<<"\n";
g<<"cost 1 -> "<<v[minim][q]<<" = "<<c[minim][q]<<"\n";g<<"\n";*/
if ( d[v[minim][q]] > d[minim] + c[minim][q])
{
d[v[minim][q]] = d[minim] + c[minim][q];
if (poz[v[minim][q]] != -1)
perc(poz[v[minim][q]]);
else
{
H[++h]=v[minim][q];
poz[H[h]]=h;
sift(h);
}
}
afis();
}
}
}
int main()
{
f>>n>>m;
for(i=1;i<=m;i++)
{
f>>a>>b>>x;
v[a].pb(b);
c[a].pb(x);
}
dijkstra_heap();
//for(i=2;i<=n;i++) if(d[i]==inf) g<<"0 "; else g<<d[i]<<" "; g<<"\n";
f.close();
g.close();
return 0;
}