PermCheck

Python

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    # write your code in Python 3.6
    permutation = [i for i in range(0, len(A) + 1)]

    for a in A:
        if a >= len(permutation):
            return 0
        permutation[a] = 0

    return 0 if len([i for i in permutation if i != 0]) > 0 else 1