import core.thread;
import std.conv, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.container, std.math, std.range, std.regex;
import core.bitop;

//	Input
class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { tokens = readln.split; if (stdin.eof) throw new EOFException; } auto token = tokens[0]; tokens.popFront; return token; }
int readInt() { return to!int(readToken); }
long readLong() { return to!long(readToken); }
real readReal() { return to!real(readToken); }

//	chmin/chmax
void chmin(T)(ref T t, in T f) { if (t > f) t = f; }
void chmax(T)(ref T t, in T f) { if (t < f) t = f; }

//	Pair
struct Pair(S, T) {
	S x; T y;
	int opCmp(    const Pair p) const { return (x < p.x) ? -1 : (x > p.x) ? +1 : (y < p.y) ? -1 : (y > p.y) ? +1 : 0; }
	int opCmp(ref const Pair p) const { return (x < p.x) ? -1 : (x > p.x) ? +1 : (y < p.y) ? -1 : (y > p.y) ? +1 : 0; }
	string toString() const { return "(" ~ to!string(x) ~ ", " ~ to!string(y) ~ ")"; }
}
auto pair(S, T)(inout(S) x, inout(T) y) { return Pair!(S, T)(x, y); }

//	Array
int binarySearch(T)(in T[] as, in bool delegate(T) test) { int low = -1, upp = as.length; for (; low + 1 < upp; ) { int mid = (low + upp) >> 1; (test(as[mid]) ? low : upp) = mid; } return upp; }
int lowerBound(T)(in T[] as, in T val) { return as.binarySearch((T a) { return (a <  val); }); }
int upperBound(T)(in T[] as, in T val) { return as.binarySearch((T a) { return (a <= val); }); }
T[] unique(T)(in T[] as) { T[] bs; foreach (a; as) if (bs.empty || bs[$ - 1] != a) bs ~= a; return bs; }


int N, M, K;
int[] A, B, C;
int[] T;

void main(string[] args) {
	try {
	for (; ; ) {
		N = readInt;
		M = readInt;
		K = readInt;
		A = new int[M];
		B = new int[M];
		C = new int[M];
		foreach (i; 0 .. M) {
			A[i] = readInt - 1;
			B[i] = readInt - 1;
			C[i] = readInt;
		}
		T = new int[K];
		foreach (k; 0 .. K) {
			T[k] = readInt - 1;
		}
		
		bool[] isT = new bool[N];
		foreach (t; T) {
			isT[t] = true;
		}
		int[] nonTs;
		foreach (u; 0 .. N) if (!isT[u]) {
			nonTs ~= u;
		}
		
		int[][] D = new int[][](N, N);
		foreach (u; 0 .. N) {
			D[u][] = int.max / 2;
			D[u][u] = 0;
		}
		foreach (i; 0 .. M) {
			chmin(D[A[i]][B[i]], C[i]);
			chmin(D[B[i]][A[i]], C[i]);
		}
		foreach (w; 0 .. N) foreach (u; 0 .. N) foreach (v; 0 .. N) {
			chmin(D[u][v], D[u][w] + D[w][v]);
		}
		
		if (K == 1) {
			writeln(0);
			continue;
		} else if (K == 2) {
			writeln(D[T[0]][T[1]]);
			continue;
		}
		
		int ans = int.max;
		foreach (L; 0 .. K - 2) if (L <= N - K) {
			bool[] flg = new bool[N - K];
			flg[N - K - L .. $] = true;
			do {
				int[] us = T;
				foreach (j, u; nonTs) {
					if (flg[j]) {
						us ~= u;
					}
				}
				int sum;
				int[] ds = new int[K + L];
				bool[] vis = new bool[K + L];
				foreach (x; 1 .. K + L) {
					ds[x] = D[us[0]][us[x]];
				}
				foreach (iter; 1 .. K + L) {
					int opt = int.max;
					int xm = void;
					foreach (x; 1 .. K + L) if (!vis[x]) {
						if (opt > ds[x]) {
							opt = ds[x];
							xm = x;
						}
					}
					if (ans <= sum + ds[xm] * (K + L - iter)) {
						goto failed;
					}
					sum += ds[xm];
					vis[xm] = true;
					const Dx = D[us[xm]];
					foreach (y; 1 .. K + L) if (!vis[y]) {
						chmin(ds[y], Dx[us[y]]);
					}
				}
debug{
writeln(flg," ",us," ",sum);
}
				chmin(ans, sum);
			failed:
			} while (flg.nextPermutation);
		}
		if (K - 2 <= N - K) {
			const L = K - 2;
			bool[] flg = new bool[N - K];
			flg[N - K - L .. $] = true;
			do {
				int[] us;
				foreach (j, u; nonTs) {
					if (flg[j]) {
						us ~= u;
					}
				}
				int sum;
				foreach (t; T) {
					int opt = int.max;
					foreach (u; us) {
						chmin(opt, D[t][u]);
					}
					sum += opt;
				}
				if (ans <= sum) {
					continue;
				}
				int[] ds = new int[L];
				bool[] vis = new bool[L];
				foreach (x; 1 .. L) {
					ds[x] = D[us[0]][us[x]];
				}
				foreach (iter; 1 .. L) {
					int xm = -1;
					foreach (x; 1 .. L) if (!vis[x]) {
						if (xm == -1 || ds[xm] > ds[x]) {
							xm = x;
						}
					}
					if (ans <= sum + ds[xm] * (L - iter)) {
						goto failed2;
					}
					sum += ds[xm];
					vis[xm] = true;
					const Dx = D[us[xm]];
					foreach (y; 1 .. L) if (!vis[y]) {
						chmin(ds[y], Dx[us[y]]);
					}
				}
				chmin(ans, sum);
			failed2:
			} while (flg.nextPermutation);
		}
		writeln(ans);
	}
	} catch (EOFException) {}
}