Python的循環(huán)有兩種,一種是for...in循環(huán),依次把list或tuple中的每個(gè)元素迭代出來(lái),看例子:
names = ['Michael', 'Bob', 'Tracy']
for name in names:
print(name)
sum = 0
for x in [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]:
sum = sum + x
print(sum)
# Python提供一個(gè)range()函數(shù),可以生成一個(gè)整數(shù)序列,再通過(guò)list()函數(shù)可以轉(zhuǎn)換為list。
>>> list(range(5))
[0, 1, 2, 3, 4]
# range(101)就可以生成0-100的整數(shù)序列,計(jì)算如下:
sum = 0
for x in range(101):
sum = sum + x
print(sum)
第二種循環(huán)是while循環(huán),只要條件滿足,就不斷循環(huán),條件不滿足時(shí)退出循環(huán)。
sum = 0
n = 99
while n > 0:
sum = sum + n
n = n - 2
print(sum)
break
n = 1
while n <= 100:
if n > 10: # 當(dāng)n = 11時(shí),條件滿足,執(zhí)行break語(yǔ)句
break # break語(yǔ)句會(huì)結(jié)束當(dāng)前循環(huán)
print(n)
n = n + 1
print('END')
continue
n = 0
while n < 10:
n = n + 1
if n % 2 == 0: # 如果n是偶數(shù),執(zhí)行continue語(yǔ)句
continue # continue語(yǔ)句會(huì)直接繼續(xù)下一輪循環(huán),后續(xù)的print()語(yǔ)句不會(huì)執(zhí)行
print(n)