#include <stdio.h>

const int bit[13] = {1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096};

typedef struct {
	int key, id[2];
} data;

typedef struct {
	data obj[40000000];
	int size;
} min_heap;

void push(min_heap* h, data x)
{
	int i = ++(h->size), j = i >> 1;
	data tmp;
	h->obj[i] = x;
	while (j > 0) {
		if (h->obj[i].key < h->obj[j].key) {
			tmp = h->obj[j];
			h->obj[j] = h->obj[i];
			h->obj[i] = tmp;
			i = j;
			j >>= 1;
		} else break;
	}
}

data pop(min_heap* h)
{
	int i = 1, j = 2;
	data output = h->obj[1], tmp;
	h->obj[1] = h->obj[(h->size)--];
	while (j <= h->size) {
		if (j < h->size && h->obj[j^1].key < h->obj[j].key) j ^= 1;
		if (h->obj[j].key < h->obj[i].key) {
			tmp = h->obj[j];
			h->obj[j] = h->obj[i];
			h->obj[i] = tmp;
			i = j;
			j <<= 1;
		} else break;
	}
	return output;
}

typedef struct Edge {
	struct Edge *next;
	int v, cost, flag;
} edge;

int main()
{
	int i, j, N, M, K, u, w, c, R[12];
	edge *adj[10001] = {}, e[40001], *p;
	scanf("%d %d %d", &N, &M, &K);
	for (i = 0; i < K; i++) scanf("%d", &(R[i]));
	for (i = 0; i < M; i++) {
		scanf("%d %d %d", &u, &w, &c);
		e[i*2].v = w;
		e[i*2+1].v = u;
		e[i*2].cost = c;
		e[i*2+1].cost = c;
		e[i*2].flag = 0;
		e[i*2+1].flag = 0;
		for (j = 0; j < K; j++) {
			if (R[j] == i + 1) {
				e[i*2].flag = bit[j];
				e[i*2+1].flag = bit[j];
			}
		}
		e[i*2].next = adj[u];
		e[i*2+1].next = adj[w];
		adj[u] = &(e[i*2]);
		adj[w] = &(e[i*2+1]);
	}
	
	const int sup = ((1 << 30) - 1) << 1;
	int dist[10001][4096];
	data d;
	min_heap h;
	h.size = 0;
	for (u = 1; u <= N; u++) for (i = 0; i < bit[K]; i++) dist[u][i] = sup;
	dist[1][0] = 0;
	d.key = 0;
	d.id[0] = 1;
	d.id[1] = 0;
	push(&h, d);
	while (h.size > 0) {
		d = pop(&h);
		u = d.id[0];
		i = d.id[1];
		if (d.key != dist[u][i]) continue;
		for (p = adj[u]; p != NULL; p = p->next) {
			w = p->v;
			j = i | p->flag;
			if (dist[w][j] > dist[u][i] + p->cost) {
				dist[w][j] = dist[u][i] + p->cost;
				d.key = dist[w][j];
				d.id[0] = w;
				d.id[1] = j;
				push(&h, d);
			}
		}
	}
	printf("%d\n", dist[N][bit[K]-1]);
	fflush(stdout);
	return 0;
}