import heapq, sys
from collections import defaultdict

input = sys.stdin.read
data = input().split()

N, M, L, S, E = map(int, data[:5])
paths = [(int(data[i]), int(data[i+1]), int(data[i+2])) for i in range(5, 5 + 3 * M, 3)]
toilets = list(map(int, data[5 + 3 * M:]))

g = defaultdict(dict)
for a, b, t in paths:
    g[a][b] = min(g[a].get(b, float('inf')), t)
    g[b][a] = min(g[b].get(a, float('inf')), t)

def dijkstra(g, start):
    d = {i: float('inf') for i in g}
    d[start] = 0
    q = [(0, start)]
    while q:
        cd, cn = heapq.heappop(q)
        if cd > d[cn]: continue
        for n, w in g[cn].items():
            dist = cd + w
            if dist < d[n]:
                d[n] = dist
                heapq.heappush(q, (dist, n))
    return d

try:
    mt = dijkstra(g, 1)
    rg = defaultdict(dict)
    for a in g:
        for b in g[a]:
            rg[b][a] = g[a][b]
    mf = dijkstra(rg, N)
    min_t = float('inf')
    for t in toilets:
        at = mt[t]
        if at < S:
            tt = S + 1 + mf[t]
        elif at <= S + E - 0.99:
            tt = at + 1 + mf[t]
        else:
            continue
        if tt < min_t:
            min_t = tt
    print(-1 if min_t == float('inf') else int(min_t))
except KeyError:
    print(-1)