一、while循环:
1、 1+2+..100
i = 1
sum = 0
while i <=100:
sum = sum + i
i = i + 1
print(sum)
F:\python3.6\python.exe F:/python_workdir/oldboy/while.py
5050
2、while 的跳出循环
方法一:通过break
方法二:通过增加条件
i = 1
while i <=6:
print(i)
i = i+1
一旦遇到break,就立马跳出循环,不在执行后面的语句
i = 1
while True:
print(i)
i = i+1
if i >=6:
break
3、while之continue:
count=0
while count <=100:
count = count + 1
if count > 5 and count < 95:
continue
print("loop" , count)
print("______the end ________")
执行结果:
F:\python3.6\python.exe F:/python_workdir/oldboy/while.py
loop 1
loop 2
loop 3
loop 4
loop 5
loop 95
loop 96
loop 97
loop 98
loop 99
loop 100
loop 101
______the end ________
continue的意思是遇到它就立即结束本次循环(不是终止循环),然后开始返回继续下一次的循环,所以当count=6的时候,第一次遇到continue,结束本次循环,后面的语句不在执行,所以没打印,继续下一次的循环
continue就是“见底”
使用while打印1 2 3 4 5 6 8 9 10 (没有7)
count=0
while count <10:
count = count + 1
if count == 7:
continue
else:
print(count)
这里的continue也可替换为pass,这也是个关键字,遇到pass什么都不执行