#include <cstdio>
#include <cstring>

const int INF = int(2e9);
int N , M , K , C[16] , D[2002][2002] , ans = INF;
int sol[16] , use[16] , cost;

static inline int min(int a,int b) { return a < b ? a : b;}

void back(int k)
{
	if(k == K + 1)
		ans = min(ans,cost + D[C[sol[K]]][N]);
	else
	for(int i = 1;i<=K;++i)
		if(use[i] == 0)
		{
			int c = D[C[sol[k-1]]][C[i]];
			use[i] = 1;
			sol[k] = i;
			cost = cost + c;
			back(k+1);
			cost = cost - c;
			use[i] = 0;
		}
}

void roy_floyd()
{
	for(int k = 1;k<=N;++k)
		for(int i = 1;i<=N;++i)
			if(k!=i)
			for(int j = 1;j<=N;++j)
				if(i!=j && D[i][k] && D[k][j] && (!D[i][j] || D[i][k] + D[k][j] < D[i][j]))
					D[i][j] = D[i][k] + D[k][j];
}

void read_data()
{
	freopen("ubuntzei.in","r",stdin);
	freopen("ubuntzei.out","w",stdout);
	scanf("%d %d %d",&N,&M,&K);
	for(int i = 1;i<=K;++i)
		scanf("%d",&C[i]);
	C[0] = 1;
	int a , b ,c;
	for(;M;M--)
	{
		scanf("%d %d %d",&a,&b,&c);
		D[a][b] = D[b][a] = c;
	}
}

int main()
{
	read_data();
	roy_floyd();
	if(K == 0) ans = D[1][N];
	else
		back(1);
	printf("%d\n",ans);
	return 0;
}