第二章练习题8a

Posted 2021-01-24 riling

使用while循环实现输出2-3+4-5+6...+100 的和； 

 

a = 1
b = 0

while a< 100:
    a +=1
    if a%2 == 0:
        b = b+a
    else:
        b = b-a
print(b)