#!/usr/bin/env python3.8
# %%
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
import numpy as np
from scipy.sparse.csgraph import floyd_warshall

# %%
N, M, L = map(int, readline().split())
T = np.array(readline().split(), np.int64)
ABC = np.array(read().split(), np.int32)
A = ABC[::3]
B = ABC[1::3]
C = ABC[2::3]

# %%
dist = np.full((N, N), 10 ** 9, np.int64)
np.fill_diagonal(dist, 0)
dist[A - 1, B - 1] = C
dist[B - 1, A - 1] = C
dist = floyd_warshall(dist)

# %%
dist = (dist + .5).astype(np.int64)
cost = (dist * T[None, :]).sum(axis=1) * 2
if T[L - 1]:
    cost = cost - dist[L - 1, :]
    print(cost.min())
else:
    diff = dist[L - 1][None, :] - dist
    diff[:, T == 0] = dist[L - 1][:, None]
    cost += diff.min(axis=1)
    print(cost.min())