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Cod sursa(job #700317)
//O(MlogN)
#include <cstdio>
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define PB push_back
#define MKP make_pair
#define INF 0x3f3f3f3f
#define maxN 50005
int N , M , cost[maxN];
bool viz[maxN];
int H[maxN] , pozH[maxN] , dim;
vector <pair <int , int> > lista[maxN];
void push (int nod)
{
int tata = nod / 2;
if (nod == 1) return;
if (cost[H[tata]] <= cost[H[nod]]) return;
swap (H[tata] , H[nod]);
swap (pozH[H[tata]] , pozH[H[nod]]);
push (pozH[H[tata]]);
}
void pop (int nod)
{
int f1 = nod * 2;
int f2 = nod * 2 + 1;
int nodmin = nod;
if (f1 <= dim && cost[H[f1]] < cost[H[nodmin]])
nodmin = f1;
if (f2 <= dim && cost[H[f2]] < cost[H[nodmin]])
nodmin = f2;
if (nodmin == nod) return;
swap (H[nod] , H[nodmin]);
swap (pozH[H[nodmin]] , pozH[H[nod]]);
pop (pozH[H[nodmin]]);
}
void make_heap ()
{
for (int i = 1 ; i <= N ; ++i)
{
H[++dim] = i;
pozH[i] = dim;
push (dim);
}
}
int get_min ()
{
int nod = H[1];
swap (H[1] , H[dim]);
swap (pozH[H[1]] , pozH[H[dim]]);
--dim;
//pop (pozH[H[1]]);
pop (1);
return nod;
}
int main ()
{
freopen ("dijkstra.in" , "r" , stdin);
freopen ("dijkstra.out" , "w" , stdout);
scanf ("%d %d" , &N , &M);
int a , b , c;
for (int i = 1 ; i <= N ; ++i)
{
scanf ("%d %d %d" , &a , &b , &c);
lista[a].PB (MKP (b , c));
}
for (int i = 2 ; i <= N ; ++i)
cost[i] = INF;
make_heap ();
while (dim)
{
int nod = get_min ();
viz[nod] = true;
for (unsigned int i = 0 ; i < lista[nod].size () ; ++i)
{
int nodcur = lista[nod][i].first;
int costcur = lista[nod][i].second;
if (viz[nodcur]) continue;
if (cost[nodcur] <= cost[nod] + costcur) continue;
cost[nodcur] = cost[nod] + costcur;
push (pozH[nodcur]);
}
}
for (int i = 2 ; i <= N ; ++i)
if (cost[i] == INF)
printf ("0 ");
else printf ("%d " , cost[i]);
return 0;
}