Python基础–while循环
语法格式
1 | while 条件(判断 变量是否满足条件): |
- 1.定义变量,记录循环条件
- 2.执行循环判断
- 3.在循环体中,增加变量值,触发判断条件,终止循环
需求:使用while重复打印”南风”4次
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4i=0
while i <= 3:
print ("南风")
i+=1while循环累加
直接求和到100
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6sum_num = 0
i = 1
while i<= 100:
sum_num = sum_num +i
i += 1
print( sum_num)利用整除的方式进行if循环判断,取整数的形式.100以内所有偶数求和.
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7sum_num = 0
i = 1
while i<= 100:
if i % 2 == 0:
sum_num = sum_num +i
i += 1
print( sum_num)加上一点点判断对于100以内的奇数进行求和.
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7sum_num = 0
i = 1
while i<= 100:
if i % 2 != 0:
sum_num = sum_num +i
i += 1
print( sum_num)while循环嵌套
:需求:设计一个简单的钟表从00:00开始计数
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19import time
# 插入时间模块
hour = 0
while hour < 24:
# 定义小时,时间上是小于24小时
mi = 0
while mi < 60:
# 定义分钟,小于60min
sec = 0
while sec < 60:
# if sec == 30:
# break
# 添加这语句之后会出现在30s跳出循环的状态
print( "%02d:%02d:%02d" % (hour,mi,sec ) )
sec += 1
time.sleep(1)
# 停顿1s 按照s的计时方式
mi += 1
hour += 1