输出最大值
print('请输入3个数:')
a = int(input())
b = int(input())
c = int(input())
if a > b and a > c:
print(a)
elif b > a and b > c:
print(b)
elif c > b and c > a:
print(c)
print('请输入3个数:')
a = int(input())
b = int(input())
c = int(input())
m = a if a > b else b if b > c else c
print(m)