Escribir un programa que determine el mayor de tres números.

ax(a, b, c):
    if a > b and a > c:
        return a
    elif b > a and b > c:
        return b
    else:
        return c

def main():
    # read the input
    n = int(input())
    a = [int(x) for x in input().split()]
    # print the result
    print(