python基本操作2（速通版）（下）

t = (1,2,3,4,5,6,55,55,7,7,5,87,2)
#count方法
print(t.count(2))
#index方法
print(t.index(2))
#下标index方法调用注意如果不存在的下标就会报错
print(t.index(10))

cl1 = []
print(cl1)
print(type(cl1))
c1 = [1]
print(c1)
print(type(c1))
#定义具有多个元素的列表
cl3 = [1,2,3,'hello',(4,5,6),['a','b','c']]
print(cl3)
print(type(cl3))
for v in cl3:
    if isinstance(v,tuple) or isinstance(v,list) or isinstance(v,str):
        for i in v:
            print(i)
    else:
        print(v)

cl4 = list()
print(cl4)
print(type(cl4))
#放入的数据需要可迭代
cl5 = list('hahaha')
print(cl5)
print(type(cl5))

cl6 = [1,2,3,4,5]
print(cl6[0])
print(cl6[1])
print(cl6[2])
print(cl6[3])
print(cl6[4])

s = 'hello'
print(s)
def revers_str(s):
    ret_s = ""
    i = len(s) - 1
   #这里考虑用insert但是没有发现有
    while i >= 0:
        ret_s += s[i]
        i -= 1
    return ret_s
s = revers_str(s)
print(s)

c1 = [9,2,5,7,1,8,4,3,0,6]
print(c1)
#排序默认从小到大
c1.sort()
print("sort1:  ",c1)
#逆序/降序
c1.reverse()
print("reverse1:  ",c1)
c1 = [9,2,5,7,1,8,4,3,0,6]
#降序排序(从大到小)
print(c1)
c1.sort(reverse=True)
print("sort2:  ",c1)
#逆序是直接将原列表中的顺序进行逆序的
c1.reverse()
print("reverse2:  ",c1)

c1 = [9,2,5,7,1,8,4,3,0,6]
print(c1)
def reverse_list(c1):
    ret_1 = []
    i = len(c1) -1
    while i >= 0:
        ret_1.append(c1[i])
        i -= 1
    #ret_1不是全局变量，所以返回
    return ret_1
ret = reverse_list(c1)
print(ret)

c1 = []
#添加不同类型
c1.append(1)
c1.append(2)
c1.append(3)
c1.append('hello')
print(c1)
#添加列表
c1.append(['a','b','c'])
print(c1)
print("_______________________________________________________________")
#extend()扩展,append添加对象会出现多维的现象
cl1 = [1,2,3]
cl2 = ['a','b','c']
cl1.append(cl2)
print(cl1)
print("_______________________________________________________________")
#extend不会出现多维的现象
cl1 = [1,2,3]
cl2 = ['a','b','c']
cl1.extend(cl2)
print(cl1)
print(cl2)
print("_______________________________________________________________")
#insert 插入
#指定插入下标
cl3 = [1,2,3,4,5]
cl3.insert(2,999)
print(cl3)
#超出下标上限会默认添加到最后一位，相当于append
cl3 = [1,2,3,4,5]
cl3.insert(8,999)
print(cl3)

list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
#count()对元素个数统计
print(list1.count(6))
#index()返回元素第一个出现的位置
print(list1.index(6))
#in和not in
print(2 in list1)
print(4 not in list1)

list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
#pop返回值是删除的元素
l1 = list1.pop()
print(list1)
print(l1)
print("__________________________________________________________________")
#移除特定元素
list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
l1 = list1.remove(7)
print(list1)
print(l1)
print("_____________________________________________________________________")
list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
del list1[1]
print(list1)
print("_____________________________________________________________________")
list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
del(list1[1])
print(list1)
print("_____________________________________________________________________")
list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
list1.clear()
print(list1)
print("_____________________________________________________________________")
#在使用列表时，不要在循环遍历时删除元素
list1 = [1,2,3,4,5,6,7,6,6,6,6,6,6]
for o in list1:
    list1.remove(o)
print(list1)