#include <bits/stdc++.h>
using namespace std;
typedef unsigned long long ul;
typedef signed long long ll;
ul over = 1000000007;

int main(void)
{
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed;
  string s;
  cin >> s;
  for (auto c : s) {
    if ('a' <= c && c <= 'z') {
      cout << (char)(c-'a'+'A');
    } else {
      cout << (char)(c-'A'+'a');
    }
  }
  cout << endl;
  return 0;
}