题解 | #字符串加解密#

#include <cctype>
#include <iostream>
using namespace std;


void add_(string &str){
    for (int i = 0; i < str.size(); i++){
        if (isalpha(str[i])){
            if (str[i] == 'Z')
                str[i] = 'a';
            else if(str[i] == 'z')
                str[i] = 'A';
            else if (isupper(str[i]))
                str[i] = tolower(str[i]) + 1;
            else
                str[i] = toupper(str[i]) + 1;
        }
        else{
            if (str[i] == '9')
                str[i] = '0';
            else
                str[i] = str[i] + 1;
        }
    }
}
void readd_(string &str){
    for (int i = 0; i < str.size(); i++){
        if (isalpha(str[i])){
            if (str[i] == 'A')
                str[i] = 'z';
            else if(str[i] == 'a')
                str[i] = 'Z';
            else if (isupper(str[i]))
                str[i] = tolower(str[i]) - 1;
            else
                str[i] = toupper(str[i]) - 1;
        }
        else{
            if (str[i] == '0')
                str[i] = '9';
            else
                str[i] = str[i] - 1;
        }
    }
}
int main() {
    string str_1, str_2;
    cin>>str_1>>str_2;
    add_(str_1);
    readd_(str_2);
    cout << str_1<<endl<<str_2;
}
// 64 位输出请用 printf("%lld")