#include <bits/stdc++.h>
#define int long long
using namespace std;

signed main() {
  string S;
  cin >> S;
  
  string A = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  string a = "abcdefghijklmnopqrstuvwxyz";
  
  string ans = "";
  for( int i = 0; i < S.size(); i++ ){
    for( int j = 0; j < A.size(); j++ ){
      if( S.at(i) == A.at(j) ) ans += a.at(j);
    }
    for( int j = 0; j < a.size(); j++ ){
      if( S.at(i) == a.at(j) ) ans += A.at(j);
    }
  }
  cout << ans << endl;
}