for 循环通常用于可迭代对象的遍历。for 循环的语法格式如下:
for 变量 in 可迭代对象:
循环体语句
Python中可迭代对象:
1、序列。包含:字符串、列表、元组
2、字典
3、迭代器对象(iterator)
4、生成器函数(generator)
5、文件对象
for x in (10,20,30): #for循环遍历元组
print(x*2,end="\t")
for x in "ABCDE": #for循环遍历字符串
print(x,end="\t")
for x in list("abcde"): #for循环遍历列表
print(x,end="\t")
d={"name":"Vince","age":18,"job":"Student"}
for x in d: #for循环遍历字典
print(x)
for x in d.keys(): #for循环遍历字典的键
print(x)
for x in d.values(): #for循环遍历字典的值
print(x)
for x in d.items(): #for循环遍历字典的键值对
print(x)
#for循环遍历range()迭代对象
sum=0
sum_odd=0 #偶数和
sum_even=0 #奇数和
for x in range(101):
sum+=x
if x%2==0:
sum_odd+=x
else:
sum_even+=x
print("总数和为{0},偶数和为{1},奇数和为{2}".format(sum,sum_odd,sum_even))
转载于:https://www.jianshu.com/p/9329042c0ee0