Pagini recente » Cod sursa (job #2818337) | Cod sursa (job #1124321) | Cod sursa (job #36143) | Cod sursa (job #1491771) | Cod sursa (job #1915505)
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream f("dijkstra.in");
ofstream g("dijkstra.out");
#define inf 2000000000
vector < pair<int,int> > A[50001];
vector < pair<int,int> > :: iterator it;
int N, D[50001], H[50001], P[50001], NH;
void percolate(int x){
int p,c;
c = x;
p = c / 2;
while( p > 0 && H[p] > H[c] ){
swap(H[p], H[c]);
swap(P[p],P[c]);
c = p;
p = c / 2;
}
}
void del(){
int d, c;
c = 1;
swap(H[1],H[NH]);
swap(P[1],P[NH]);
NH--;
while(1){
d = 2 * c;
if(d > NH)
break;
if( d + 1 <= NH && H[d+1] < H[d] )
d++;
if( H[c] > H[d] ){
swap(H[c],H[d]);
swap(P[c],P[d]);
c = d;
}
else
break;
}
}
int main()
{
int m, i, x, y, c, k, ok, min;
f >> N >> m;
for(i = 1; i <= m; i++){
f >> x >> y >> c;
A[x].push_back(make_pair(y,c));
}
for( i = 1; i <= N; i++ ){
D[i] = inf;
}
D[1] = 0;
ok = 1;
NH++;
H[NH] = 0;
P[1] = 1;
while(NH > 0){
k = P[1];
del();
for( it = A[k].begin(); it < A[k].end(); it++ )
if( D[it->first] > D[k] + it->second ){
D[it->first] = D[k] + it->second;
if(P[it->first] == 0){ // nu e in heap
NH++;
H[NH] = D[k] + it->second;
P[NH] = it->first;
percolate(NH);
}
else
percolate(P[it->first]);
}
}
for(i = 2; i <= N; i++)
if(D[i] == inf)
g << "0 ";
else
g << D[i] << " ";
return 0;
}