题解 | #简单密码#

#include <iostream>
#include <string>
#include <cstdio>
using namespace std;

int main() {
    string s;
    while (getline(cin, s)) {
        if("START" == s || "END" == s){
            continue;
        }else if("ENDOFINPUT" == s){
            break;
        }else{
            for(int i = 0; i < s.size(); ++i){
                if('F' <= s[i] && s[i] <= 'Z'){
                    s[i] -= 5;
                }else if('A' <= s[i] && s[i] <= 'E'){
                    s[i] += 21;
                }
            }
        }
        cout << s << endl;
    }
}