题解

c++题解

#include <iostream>  
#include <algorithm>  
#include <string>  

int main() {  
    int X;  
    std::cin >> X;  

    std::string strX = std::to_string(X);  
    std::next_permutation(strX.begin(), strX.end());  

    // If the next permutation is still less than or equal to original X  
    if (strX > std::to_string(X)) {  
        std::cout << strX << std::endl;  
    } else {  
        std::cout << 0 << std::endl;  
    }  

    return 0;  
}