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Cod sursa(job #597148)
#include <cstdio>
#define FIN "dijkstra.in"
#define FOUT "dijkstra.out"
#define MAX_N 50005
#define INF 0x3f3f3f3
typedef struct NOD
{
int nod, cost;
NOD *next;
};
int N, M, i, k;
NOD *A[MAX_N];
int D[MAX_N]; // distante
int H[MAX_N]; // heap
int P[MAX_N];
void readdata()
{
int x, y, c, i;
scanf("%d %d", &N, &M);
for (i = 1; i <= M; ++i)
{
scanf("%d %d %d", &x, &y, &c);
NOD *q = new (NOD);
q->nod = y, q->cost = c, q->next = A[x], A[x] = q;
}
}
void lift(int c)
{
int d;
while (c > 1)
{
d = c >> 1; // fiul
if (D[ H[d] ] > D[ H[c] ])
{
P[ H[c] ] = d, P[ H[d] ] = c;
// urcam in heap
int ax = H[d]; H[d] = H[c], H[c] = ax;
// actualizam fiul
c = d;
}
else c = 1;
}
}
void sink(int c)
{
int s; // fiu
while (c << 1 <= k)
{
s = c << 1;
if ((s|1) <= k && D[ H[(s|1)] ] < D[ H[s] ]) s |= 1;
if (D[ H[s] ] < D[ H[c] ])
{
P[ H[s] ] = c, P[ H[c] ] = s;
int ax = H[s]; H[s] = H[c], H[c] = ax;
c = s;
}
else return;
}
}
// k - nr de elemente din heap
void solve()
{
int i;
// initializari
for (i = 2; i <= N; ++i)
D[i] = INF, P[i] = -1;
P[1] = 1, H[++k] = 1;
while (k)
{
int min = H[1];
// scot elementul din heap
int ax = H[1]; H[1] = H[k]; H[k] = ax;
P[H[1]] = 1;
--k, sink(1);
for (NOD *q = A[min]; q != NULL; q = q->next)
if (D[q->nod] > D[min] + q->cost)
{
D[q->nod] = D[min] + q->cost;
if (P[q->nod] != -1) lift(P[q->nod]);
else H[++k] = q->nod, P[H[k]] = k, lift(k);
}
}
}
int main()
{
freopen (FIN, "r", stdin);
freopen (FOUT, "w", stdout);
readdata();
solve();
for (i = 2; i <= N; ++i)
if (D[i] != INF) printf ("%d ", D[i]); else printf ("0 ");
return 0;
}