一、修改、添加和刪除元素
討論如何對列表中元素進行添加、刪除及修改
1.添加元素
（1）在列表末尾添加元素——append
輸入如下代碼
name=["liming","zhanghua","chenli"]
print(name)
name.append("wangcan")
print(name)
輸出結果如下
['liming', 'zhanghua', 'chenli']
['liming', 'zhanghua', 'chenli', 'wangcan']
（2）在列表中插入元素——insert
輸入如下代碼：
name=["liming","zhanghua","chenli"]
print(name)
name.insert(1,'wangcan')
print(name)
輸出結果如下圖：
['liming', 'zhanghua', 'chenli']
['liming', 'wangcan', 'zhanghua', 'chenli']
2.刪除元素
（1）使用del語句刪除元素（已知位置）
name=["liming","zhanghua","chenli"]
print(name)
del name[0]
print(name)
則會輸出如下結果：
['liming', 'zhanghua', 'chenli']
['zhanghua', 'chenli']
（2）使用方法pop刪除元素
方法pop（）可刪除列表末尾的元素，並能讓你接着使用它。
name=["liming","zhanghua","chenli"]
print(name)
popped_name=name.pop()
print(name)
print(popped_name)
輸出如下
['liming', 'zhanghua', 'chenli']
['liming', 'zhanghua']
chenli
(3)彈出列表中任何位置處的元素
可用pop刪除列表中任何位置的元素，只需在括號中加入索引
name=["liming","zhanghua","chenli"]
print(name)
popped_name=name.pop(0)
print(name)
print(popped_name)
輸出如下：
['liming', 'zhanghua', 'chenli']
['zhanghua', 'chenli']
liming
（4）根據值刪除元素（位置未知）利用方法remove()
執行以下代碼：
name = ["liming", "zhanghua", "chenli"]
print(name)
name.remove("liming")
print(name)
輸出如下：
['liming', 'zhanghua', 'chenli']
['zhanghua', 'chenli']
動手試一試 3-4到3-7代碼
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、組織列表
1.使用方法sort()對列表進行永久性排序
cars=['bmw','audi','toyota','subaru']
cars.sort()
print(cars)
列表則按首字母排序，且無法恢復。
['audi', 'bmw', 'subaru', 'toyota']
若在sort中傳遞參數reverse=True，則按與字母順序相反順序排列。
cars=['bmw','audi','toyota','subaru']
cars.sort(reverse=True)
print(cars)
輸出結果如下
['toyota', 'subaru', 'bmw', 'audi']
2.使用函數sorted()對列表進行臨時排序
sorted()可保留原排序，同時以特定方式呈現他們.
cars = ['bmw', 'audi', 'toyota', 'subaru']
print(sorted(cars))
print(cars)
輸出:
['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)
輸出結果如下：
['bmw', 'audi', 'toyota', 'subaru']
['subaru', 'toyota', 'audi', 'bmw']
4.確定列表長度——使用函數len()
cars = ['bmw', 'audi', 'toyota', 'subaru']
print(len(cars))
輸出：
4
動手試一試代碼：
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)
輸出：
['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']