1. 找到字符串中最后一個特定字符的位置：

#include <iostream>
#include <cstring>

int main() {
    const char* str = "Hello, world!";
    char ch = 'o';
    
    const char* lastOccurrence = strrchr(str, ch);
    
    if (lastOccurrence != NULL) {
        std::cout << "Last occurrence of '" << ch << "' is at position " << lastOccurrence - str << std::endl;
    } else {
        std::cout << "Character '" << ch << "' not found in the string." << std::endl;
    }
    
    return 0;
}

2. 找到文件路徑中文件名的位置：

#include <iostream>
#include <cstring>

int main() {
    const char* filePath = "C:\\Users\\user\\Documents\\file.txt";
    const char* fileName = strrchr(filePath, '\\');
    
    if (fileName != NULL) {
        std::cout << "File name is: " << fileName + 1 << std::endl; // +1 to exclude the backslash
    } else {
        std::cout << "File name not found in the path." << std::endl;
    }
    
    return 0;
}

這些示例展示了如何在C++中使用strrchr函數來查找字符串中最后一個特定字符的位置。