#include "crocodile.h"
#include <stdlib.h>
#include <string.h>
#define N 100000
#define INF 0x3f3f3f3f
int *ej[N], *ew[N], eo[N];
void append(int i, int j, int w) {
int o = eo[i]++;
if (o >= 2 && (o & o - 1) == 0) {
ej[i] = (int *) realloc(ej[i], o * 2 * sizeof *ej[i]);
ew[i] = (int *) realloc(ew[i], o * 2 * sizeof *ew[i]);
}
ej[i][o] = j, ew[i][o] = w;
}
int dd1[N], dd2[N], iq[1 + N], pq[N], cnt;
int lt(int i, int j) {
return dd2[i] < dd2[j];
}
int p2(int p) {
return (p *= 2) > cnt ? 0 : (p < cnt && lt(iq[p + 1], iq[p]) ? p + 1 : p);
}
void pq_up(int i) {
int p, q, j;
for (p = pq[i]; (q = p / 2) && lt(i, j = iq[q]); p = q)
iq[pq[j] = p] = j;
iq[pq[i] = p] = i;
}
void pq_dn(int i) {
int p, q, j;
for (p = pq[i]; (q = p2(p)) && lt(j = iq[q], i); p = q)
iq[pq[j] = p] = j;
iq[pq[i] = p] = i;
}
void pq_add_last(int i) {
iq[pq[i] = ++cnt] = i;
}
int pq_remove_first() {
int i = iq[1], j = iq[cnt--];
if (j != i)
pq[j] = 1, pq_dn(j);
pq[i] = 0;
return i;
}
int travel_plan(int n, int m, int ij[][2], int *ww, int k, int *ii) {
int h, i, j;
for (i = 0; i < n; i++) {
ej[i] = (int *) malloc(2 * sizeof *ej[i]);
ew[i] = (int *) malloc(2 * sizeof *ew[i]);
}
for (h = 0; h < m; h++) {
i = ij[h][0], j = ij[h][1];
append(i, j, ww[h]), append(j, i, ww[h]);
}
memset(dd1, 0x3f, n * sizeof *dd1), memset(dd2, 0x3f, n * sizeof *dd2);
for (h = 0; h < k; h++) {
i = ii[h];
dd1[i] = dd2[i] = 0, pq_add_last(i);
}
while (cnt) {
int o;
i = pq_remove_first();
if (i == 0)
return dd2[i];
for (o = eo[i]; o--; ) {
int j = ej[i][o], w = ew[i][o], d = dd2[i] + w;
if (dd1[j] > d) {
if (dd2[j] == INF && dd1[j] != INF)
pq_add_last(j);
dd2[j] = dd1[j], dd1[j] = d, pq_up(j);
} else if (dd2[j] > d) {
if (dd2[j] == INF)
pq_add_last(j);
dd2[j] = d, pq_up(j);
}
}
}
return -1;
}
