#include <iostream>
#include <string>

using namespace std;

int main(){

   string s;

   cin >> s;

   for(int i = 0; i < s.length(); i++){
      if('a' <= s[i] && s[i] <= 'z'){
         cout << (char)('A' + (s[i] - 'a')); 
      }
      else{
         cout << (char)('a' + (s[i] - 'A'));
      }
   }

   cout << endl;

   return 0;
}