for…in循环
依次把List或者Tuple中的每个元素迭代出来:
>>> names = ['Michael', 'Bob', 'Tracy']
>>> for name in names:
print(name)
Michael
Bob
Tracy
range()函数:可以生成一个整数序列,通过list()函数可以转换成List
>>> list(range(10))
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> sum = 0
>>> for x in range(101):
sum = sum + x
>>> print(sum)
5050
while循环
只要条件满足,就不断循环,条件不满足时退出循环
>>> sum = 0
>>> n = 99
>>> while n>0:
sum = sum + n
n = n -2
>>> print(sum)
2500
break和continue的使用:
break:提前退出循环
>>> n = 1
>>> while n <= 100:
if n > 2: # 当n = 11时,条件满足,执行break语句
break # break语句会结束当前循环
print(n)
n = n + 1
print('END')
1
END
2
END
continue:提前结束本轮循环,并直接开始下一轮循环。
>>> n = 0
>>> while n < 10:
n = n + 1
if n % 2 == 0: # 如果n是偶数,执行continue语句
continue # continue语句会直接继续下一轮循环,后续的print()语句不会执行
print(n)
1
3
5
7
9