Python学习【第2篇】：循环

For循环

pass

while 循环

pass

练习题：

1.使用while循环输入 1 2 3 4 5 6 8 9 10，不输出7

n = 1
while n< 11:
    if n == 7:
        pass
    else:
        print(n)
    n = n + 1
print ("运行结束")
注意：代码块的缩进

2.输出1-100内所有奇数

n = 1
while n < 101:
    if n % 2 == 0:
        pass
    else:
        print(n)
    n = n + 1
print("运行结束")

3.输出1-100内所有偶数

n = 1
while n < 101:
    if n % 2 == 0:
        print(n)
    else:
        pass
    n = n + 1print("运行结束")

4.求1-100内数相加的和

n = 1
s = 0
while n < 101:
    s = s + n
    n = n + 1
print(s)

5.求1-2+3-4+5-6+.........99数之和

n = 1
s = 0
while n < 99:
    temp = n % 2
    if temp == 0:
        s = s - n
    else:
        s = s + n
    n = n + 1
print(s)
6、用户登陆（三次机会重试）

巴特西