import sys
from itertools import starmap
from operator import mul

N, M, L = map(int, input().split())
L -= 1
t = list(map(int, input().split()))
matrix = [[float("inf")]*N for _ in [0]*N]
for i in range(N):
    matrix[i][i] = 0

for a, b, c in ((map(int, l.split())) for l in sys.stdin):
    matrix[a-1][b-1] = matrix[b-1][a-1] = c

def warshall_floyd(v_count: int, matrix: list) -> list:
    """ ワーシャルフロイド
    :param v_count: 頂点数
    :param matrix: 隣接行列(到達不能はfloat("inf"))
    """
    # 到達不能をfloat("inf")にしておけば余計なチェックを入れなくても
    # inf > inf+(-1) のような到達不能＋負辺が繋がってしまうことはない
    for i in range(v_count):
        for j, c2 in enumerate(row[i] for row in matrix):
            for k, (c1, c3) in enumerate(zip(matrix[j], matrix[i])):
                if c1 > c2+c3:
                    matrix[j][k] = c2+c3
    return matrix

edges = warshall_floyd(N, matrix)

ans = float("inf")
for i in range(N):
    cost = sum(starmap(mul, zip(matrix[i], t))) * 2
    if t[L] > 0:
        cost -= matrix[i][L]
    else:
        cost += min(matrix[i][L], min(matrix[L][j]-matrix[j][i] for j in range(N) if t[j]))
    if ans > cost:
        ans = cost

print(ans)