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])