easy

#include<iostream>
#include<string>
using namespace std;
int main()
{
    string s,st;
    int ii;
    getline(cin,s);
    for(int i = 0;i < s.size();i++){s[i]+=3;if(!((s[i] >= 'A' && s[i] <= 'Z')||(s[i] >= 'a' && s[i] <= 'z')))s[i] -= 26;;}
    st = s;
    ii = 0;
    for(int i = s.size()-1;i >= 0;i--){s[i] = st[ii];ii++;}
    for(int i = 0;i < s.size();i++){if(s[i] >= 'A' && s[i] <= 'Z')s[i] += 32;else s[i] -= 32;}
    cout << s;
    return 0;
}