python推导式

li = []
for i in range(0,5):
    li.append(i)

li1 = [ i for i in range(0,5)]
print(li) #[0, 1, 2, 3, 4]
print(li1) #[0, 1, 2, 3, 4]

li = []
for i in range(0,5):
    if i % 2 == 0:
        li.append(i)

li1 = [ i for i in range(0,5) if i % 2 == 0]
print(li) # [0, 2, 4]
print(li1) # [0, 2, 4]

li = [‘电脑‘,‘手机‘,‘平板‘]
dic = {key: value for value,key in enumerate(li)}
print(dic) # {‘电脑‘: 0, ‘手机‘: 1, ‘平板‘: 2}

li = [1,2,3]
li1 = [4,5,6]
di = { li[i] : li1[i] for i in range(len(li))}
print(di) # {1: 4, 2: 5, 3: 6}

dic = {‘张三‘:17,"李四":18,"王五":19}
dic1 = { key:value for key,value in dic.items() if value >= 18}
print(dic1) # {‘李四‘: 18, ‘王五‘: 19}