for循环&生成器&map

 1 def add(x,y):
 2     print(x+y)
 3     #return x+y
 4 x = [1,2,3]
 5 y = [4,5,6]
 6 print(‘type(zip(x,y)):‘,type(zip(x,y)))#zip class
 7 print(‘for i,j in zip(x,y)‘)
 8 for i,j in zip(x,y):
 9     print(i+j)
10 print(‘for i,j in [(1,5),(2,6),(3,7)]‘)
11 for i,j in [(1,5),(2,6),(3,7)]:
12     print(i+j)               #print 6,8,10
13 def gen(func,a,b):           #a,b为列表
14     for item1, item2 in zip(a,b):
15         yield func(item1,item2)
16 print(‘for i in gen(add,x,y)‘)
17 print(‘type(gen(add,x,y):)‘,type(gen(add,x,y)))#generator class
18 for i in gen(add,x,y):       #把func结果一次次迭代出来
19 
20     i                        #print 5,7,9
21     #print(i)
22 result = map(lambda x,y:print(x+y),x,y)#返回元素为lambda结果的迭代器类
23 print(‘for i in map(lambda x,y:print(x+y),x,y)‘)
24 for i in result:
25     i
26     #print(i)#用于map(lambda x,y:x+y,x,y)