一、修改、添加和删除元素
讨论如何对列表中元素进行添加、删除及修改
1.添加元素
（1）在列表末尾添加元素——append
输入如下代码
name=["liming","zhanghua","chenli"]
print(name)
name.append("wangcan")
print(name)
输出结果如下
['liming', 'zhanghua', 'chenli']
['liming', 'zhanghua', 'chenli', 'wangcan']
（2）在列表中插入元素——insert
输入如下代码：
name=["liming","zhanghua","chenli"]
print(name)
name.insert(1,'wangcan')
print(name)
输出结果如下图：
['liming', 'zhanghua', 'chenli']
['liming', 'wangcan', 'zhanghua', 'chenli']
2.删除元素
（1）使用del语句删除元素（已知位置）
name=["liming","zhanghua","chenli"]
print(name)
del name[0]
print(name)
则会输出如下结果：
['liming', 'zhanghua', 'chenli']
['zhanghua', 'chenli']
（2）使用方法pop删除元素
方法pop（）可删除列表末尾的元素，并能让你接着使用它。
name=["liming","zhanghua","chenli"]
print(name)
popped_name=name.pop()
print(name)
print(popped_name)
输出如下
['liming', 'zhanghua', 'chenli']
['liming', 'zhanghua']
chenli
(3)弹出列表中任何位置处的元素
可用pop删除列表中任何位置的元素，只需在括号中加入索引
name=["liming","zhanghua","chenli"]
print(name)
popped_name=name.pop(0)
print(name)
print(popped_name)
输出如下：
['liming', 'zhanghua', 'chenli']
['zhanghua', 'chenli']
liming
（4）根据值删除元素（位置未知）利用方法remove()
执行以下代码：
name = ["liming", "zhanghua", "chenli"]
print(name)
name.remove("liming")
print(name)
输出如下：
['liming', 'zhanghua', 'chenli']
['zhanghua', 'chenli']
动手试一试 3-4到3-7代码
name=["Zhangsan","Lisi","Wangwu"]
invitation1=name[0]+","+"welcome to my party"+"!"
invitation2=name[1]+","+"welcome to my party"+"!"
invitation3=name[2]+","+"welcome to my party"+"!"
print(invitation1)
print(invitation2)
print(invitation3)
print("\n")
explain1="Zhangsan can't come."
print(explain1)
name[0]="chenliu"
invitation1=name[0]+","+"welcome to my party"+"!"
invitation2=name[1]+","+"welcome to my party"+"!"
invitation3=name[2]+","+"welcome to my party"+"!"
print(invitation1)
print(invitation2)
print(invitation3)
print("\n")
print("I find a bigger table")
name.insert(0,"a")
name.insert(2,"b")
name.append('c')
invitation1=name[0]+","+"welcome to my party"+"!"
invitation2=name[1]+","+"welcome to my party"+"!"
invitation3=name[2]+","+"welcome to my party"+"!"
invitation4=name[3]+","+"welcome to my party"+"!"
invitation5=name[4]+","+"welcome to my party"+"!"
invitation6=name[5]+","+"welcome to my party"+"!"
print(invitation1)
print(invitation2)
print(invitation3)
print(invitation4)
print(invitation5)
print(invitation6)
print("\n")
print("no new table,just two guests")
popped_name=name.pop()
print(popped_name+",sorry,you can not come")
popped_name=name.pop()
print(popped_name+",sorry,you can not come")
popped_name=name.pop()
print(popped_name+",sorry,you can not come")
popped_name=name.pop()
print(popped_name+",sorry,you can not come")
print(name[0]+",you are still in the list")
print(name[1]+",you are still in the list")
del name[0]
del name[0]
print(name)
二、组织列表
1.使用方法sort()对列表进行永久性排序
cars=['bmw','audi','toyota','subaru']
cars.sort()
print(cars)
列表则按首字母排序，且无法恢复。
['audi', 'bmw', 'subaru', 'toyota']
若在sort中传递参数reverse=True，则按与字母顺序相反顺序排列。
cars=['bmw','audi','toyota','subaru']
cars.sort(reverse=True)
print(cars)
输出结果如下
['toyota', 'subaru', 'bmw', 'audi']
2.使用函数sorted()对列表进行临时排序
sorted()可保留原排序，同时以特定方式呈现他们.
cars = ['bmw', 'audi', 'toyota', 'subaru']
print(sorted(cars))
print(cars)
输出:
['audi', 'bmw', 'subaru', 'toyota']
['bmw', 'audi', 'toyota', 'subaru']
3.倒着打印列表——使用方法reverse()
cars = ['bmw', 'audi', 'toyota', 'subaru']
print(cars)
cars.reverse()
print(cars)
输出结果如下：
['bmw', 'audi', 'toyota', 'subaru']
['subaru', 'toyota', 'audi', 'bmw']
4.确定列表长度——使用函数len()
cars = ['bmw', 'audi', 'toyota', 'subaru']
print(len(cars))
输出：
4
动手试一试代码：
cities=['France','Iceland','New Zealand','America','Britain']
print(cities)
print(sorted(cities))
print(cities)
print(sorted(cities,reverse=True))
print(cities)
cities.reverse()
print(cities)
cities.reverse()
print(cities)
cities.sort()
print(cities)
cities.sort(reverse=True)
print(cities)
输出：
['France', 'Iceland', 'New Zealand', 'America', 'Britain']
['America', 'Britain', 'France', 'Iceland', 'New Zealand']
['France', 'Iceland', 'New Zealand', 'America', 'Britain']
['New Zealand', 'Iceland', 'France', 'Britain', 'America']
['France', 'Iceland', 'New Zealand', 'America', 'Britain']
['Britain', 'America', 'New Zealand', 'Iceland', 'France']
['France', 'Iceland', 'New Zealand', 'America', 'Britain']
['America', 'Britain', 'France', 'Iceland', 'New Zealand']
['New Zealand', 'Iceland', 'France', 'Britain', 'America']