def extract_arguments(fh):
    N = int(fh.readline().strip())
    A = list(map(int, fh.readline().strip().split()))
    cables = [tuple(map(int, fh.readline().strip().split())) for _ in range(N - 1)]
    return (N, A, cables)

# if __name__ == "__main__":
#     input_path = sys.argv[1]
#     with open(input_path, 'r') as fh: 
#         N, A, cables = extract_arguments(fh)
#         f(N, A, cables)