Python基础知识：while循环

1、在循环中使用continue输出1-10之间的奇数

num=0
while num <10:
    num += 1
    if num %2 == 0: #--%--运算符，相除返回余数
        continue
    print(num)

2、使用 active = True\False 设置循环标志

#调查用户梦想的度假胜地
responses={}
name=input("What's your name?")
resort=input("What's your dream resort?")
polling_active=True
while polling_active:
    responses[name]=resort
    repeat=input("Would you like to let another person respond?(yes/no)")
    if repeat == 'no':
        polling_active = False
print('\n=== Poll Results ===')
for name,resort in responses.items():
    print(name+"'s dream resort is %s."%resort)    

3、使用break退出循环

prompt='please input some pizza toppings:'
prompt += "\nEnter 'quit' when you are finished."
toppings=''
while toppings != 'quit':
    toppings=input(prompt)
    if toppings != 'quit':
        print("we'll add some "+str(toppings)+" to pizza!")
    else:
        break

4、避免无限循环

x = 1
while x < 5:
    print(x)
    x += 1  #此处必不可少

5、while循环与if-else语句结合使用

#while循环求64是2的几次方
a = 64
i = 0
while True:
    a /= 2
    i += 1
    if a == 1:
        print(i)
        break
    else:
        continue