def func_a(arr, n):
    ret = []
    for x in arr:
        if x != n:
            ret.append(x)
    return ret

def func_b(a, b):
    if a >= b:
        return a - b
    else:
        return b - a

def func_c(arr):
    ret = -1
    for x in arr:
        if ret < x:
            ret = x
    return ret

def solution(visitor):
		# 코드 작성

print(solution([4,7,2,9,3])