如何在Python中以相反的顺序迭代一个序列?
Python 序列包括字符串、列表、元组等。我们可以使用不同的方式合并 Python 序列的元素。让我们看一些以相反顺序迭代列表的示例。
使用while循环以逆序迭代
示例
在这个例子中,我们有一个作为序列的列表,并使用while循环以相反的顺序进行迭代 -
# Creating a Listmylist = ["Jacob", "Harry", "Mark", "Anthony"]# Displaying the Listprint("List = ",mylist)# Length - 1i = len(mylist) - 1# Iterate in reverse orderprint("Display the List in Reverse order = ")while i >= 0 : print(mylist[i]) i -= 1
输出
List = ['Jacob', 'Harry', 'Mark', 'Anthony']Display the List in Reverse order = AnthonyMarkHarryJacob
使用for循环以逆序迭代
示例
在这个例子中,我们有一个作为序列的列表,并使用for循环以相反的顺序进行迭代-
# Creating a Listmylist = ["Jacob", "Harry", "Mark", "Anthony"]# Displaying the Listprint("List = ",mylist)# Iterate in reverse orderprint("Display the List in Reverse order = ")for i in range(len(mylist) - 1, -1, -1): print(mylist[i])
输出
List = ['Jacob', 'Harry', 'Mark', 'Anthony']Display the List in Reverse order = AnthonyMarkHarryJacob
使用reverse()逆序迭代
示例
在这个例子中,我们有一个List作为一个序列,并使用reversed()方法以相反的顺序进行迭代 -
立即学习“Python免费学习笔记(深入)”;
# Creating a Listmylist = ["Jacob", "Harry", "Mark", "Anthony"]# Displaying the Listprint("List = ",mylist)# Iterate in reverse order using reversed()print("Display the List in Reverse order = ")[print (i) for i in reversed(mylist)]
输出
List = ['Jacob', 'Harry', 'Mark', 'Anthony']Display the List in Reverse order = AnthonyMarkHarryJacob
使用负索引进行反向迭代
示例
在此示例中,我们将 List 作为序列,并使用负索引以相反顺序迭代它 −
# Creating a Listmylist = ["Jacob", "Harry", "Mark", "Anthony"]# Displaying the Listprint("List = ",mylist)# Iterate in reverse order using negative indexingprint("Display the List in Reverse order = ")[print (i) for i in mylist[::-1]]
输出
List = ['Jacob', 'Harry', 'Mark', 'Anthony']Display the List in Reverse order = AnthonyMarkHarryJacob