#include<iostream>
#include<string>

using namespace std;

int main(){
  string s;
  cin >> s;
  for(int i=0; i < s.length(); i++){
    if(s[i] >= 'a'){
      s[i] -= 32;
    }
    else{
      s[i] += 32;
    }
  }
  cout << s << endl;
  return 0;
}