python 基础(三)

tuple: 元组被定义后无法被修改

count():

 #count(obj) 统计obj在元组中出现的次数
 tup = (1,2,3,4,5,6,5,5,5,5,5,5,5)
 print(tup.count(6))

len():

 #len(tuple) 统计tuple的元素个数
 tup = (1,2,3,4,5,6,7,8)
 print(len(tup))

index():

 #index(x,[start,[end]]) 返回x在tuple中第一次出现的索引
 tup = (1,2,3,4,5,6,7,8)
 x = tup.index(2)

dictionary: 字典里的键值对是无序的

 dict = {1:'qq',2:'mm',3:'kk'}
 #添加元素
 dict[4] = 'yy'
 #删除元素
 del dict[1]
 #修改元素
 dict[2] = 'hh'