太难了啊啊啊

#include <iostream>  
#include <string>  
using namespace std;  
char encryptChar(char c) {  
    if (c >= 'A' && c <= 'Z') { 
        if (c + 3 > 'Z') {  
            return c - 23; 
        } else {  
            return c + 3;  
        }  
    } else if (c >= 'a' && c <= 'z') { 
        if (c + 3 > 'z') {  
            return c - 23; 
        } else {  
            return c + 3;  
        }  
    }   
    return c;  
}  
string encryptString(const string& input) {  
    string encrypted = "";  
    for (char c : input) {  
        encrypted += encryptChar(c);  
    }  
    return encrypted;  
}  
  
int main() {  
    string input;  
    getline(cin, input);  
    cout << encryptString(input) << endl;  
    return 0;  
}