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Cod sursa(job #383964)
#include <stdio.h>
#include <vector>
#define NMAX 50001
#define INF 1000000000
#define pb push_back
#define mp make_pair
#define f first
#define s second
using namespace std;
int n,m,r,cost[NMAX];
vector < pair <int,int> > v[NMAX];
struct heap
{
int a,b;
};
heap A[NMAX];
void read()
{
scanf("%d%d",&n,&m);
int i,x,y,z;
for (i=1; i<=m; i++)
{
scanf("%d%d%d",&x,&y,&z);
v[x].pb(mp(y,z));
}
}
void init()
{
int i;
for (i=2; i<=n; i++)
cost[i]=INF;
}
void interschimba(int x,int y)
{
int f,g;
f=A[x].a; g=A[x].b;
A[x].a=A[y].a; A[x].b=A[y].b;
A[y].a=f; A[y].b=g;
}
void muta_in_jos(int nod)
{
int minimum;
if (2*nod<=r)
{
minimum=nod;
if (A[2*nod].b<A[nod].b)
minimum=2*nod;
if (2*nod+1<=r && A[2*nod+1].b<A[minimum].b)
minimum=2*nod+1;
if (minimum!=nod)
{
interschimba(nod,minimum);
muta_in_jos(minimum);
}
}
}
void muta_in_sus(int nod)
{
if (nod>1 && A[nod/2].b>A[nod].b)
{
interschimba(nod/2,nod);
muta_in_sus(nod/2);
}
}
void dijkstra()
{
A[++r].a=1;
int i,x,y;
while (r)
{
x=A[1].a; y=A[1].b;
A[1]=A[r]; r--; //stergere din heap
muta_in_jos(1);
for (i=0; i<v[x].size(); i++)
if (y+v[x][i].s<cost[v[x][i].f])
{
cost[v[x][i].f]=y+v[x][i].s;
A[++r].a=v[x][i].f; //adaugare heap
A[r].b=y+v[x][i].s;
muta_in_sus(r);
}
}
}
void show()
{
int i;
for (i=2; i<=n; i++)
printf("%d ",cost[i]==INF ? 0 : cost[i]);
printf("\n");
}
int main()
{
freopen("dijkstra.in","r",stdin);
freopen("dijkstra.out","w",stdout);
read();
init();
dijkstra();
show();
return 0;
}