#include<bits/stdc++.h> using namespace std; int main(){ string a; char t; int al = a.size(); for (int i =0;i < al;i++){ t = a[i]-i; if(t >= 'a' && t<= 'z'){ t = t-32; }else{ t = t+32; } t = t - 3; } return 0; }