#include <iostream>
#include <fstream>
#include <vector>
#include <string>
using namespace std;

int main(){


  string s;
  cin >> s;
  int n = s.size();

  for (int i = 0; i < n; i++) {
    if (s[i] > 95) {
      s[i] -= 32;
    }else{
      s[i] += 32;
    }
  }
  for (int i = 0; i < n; i++) {
    cout << s[i];
  }
  cout << "\n";
  return 0;
}