Python 程序查找字符串中字符的最后出现位置

编写一个 Python 程序，通过实际示例查找字符串中字符的最后出现位置。此 Python 程序允许用户输入字符串和字符。

string = input("Please enter your own String : ")
char = input("Please enter your own Character : ")

flag = -1
for i in range(len(string)):
    if(string[i] == char):
        flag = i

if(flag == -1):
    print("Sorry! We haven't found the Search Character in this string ")
else:
    print("The Last Occurrence of ", char, " is Found at Position " , flag + 1)

首先，我们使用 For Loop 遍历字符串中的每个字符。在其中，我们使用 If statement 检查 str1 字符串中的任何字符是否等于给定字符。如果为真，则 flag = i。

接下来，我们使用 If Else Statement 检查 flag 值是否等于 -1 或不等于 0。

string = hello world
ch = l
flag = -1

For Loop 第一次迭代：for i in range(11)
if(string[i] == char)
if(h == l) – 条件为 false。

第二次迭代：for 1 in range(11)
if(e == l) – 条件为 false。

第三次迭代：for 2 in range(11)
if(str[2] == ch) => if(l == l) – 条件为 True。
flag = 2

对剩余的迭代执行相同操作。这里，条件（flag == -1）为 False。因此，else 块内的打印被执行。

Python 程序查找字符串示例 2 中字符的最后出现位置

此 Python 字符最后出现程序与上述相同。但是，我们只是将 For Loop 替换为 While Loop。

string = input("Please enter your own String : ")
char = input("Please enter your own Character : ")
i = 0
flag = -1

while(i < len(string)):
    if(string[i] == char):
        flag = i
    i = i + 1

if(flag == -1):
    print("Sorry! We haven't found the Search Character in this string ")
else:
    print("The Last Occurrence of ", char, " is Found at Position " , flag + 1)

字符串中字符的最后出现输出

Please enter your own String : tutorialgateway
Please enter your own Character : t
The Last Occurrence of  t  is Found at Position  11

Python 程序查找字符串示例 3 中字符的最后出现位置

字符串中字符的最后出现与第一个示例相同。但是，这次我们使用了 Functions 概念来分离 Python 程序逻辑。

def last_Occurrence(char, string):
    index = -1
    for i in range(len(string)):
        if(string[i] == char):
            index = i
    return index

str1 = input("Please enter your own String : ")
ch = input("Please enter your own Character : ")

flag = last_Occurrence(ch, str1)

if(flag == -1):
    print("Sorry! We haven't found the Search Character in this string ")
else:
    print("The Last Occurrence of ", ch, " is Found at Position " , flag + 1)

字符串中字符的最后出现输出

Please enter your own String : hello
Please enter your own Character : m
Sorry! We haven't found the Search Character in this string 
>>> 
Please enter your own String : python programs
Please enter your own Character : p
The Last Occurrence of  p  is Found at Position  8
>>>