#include <bits/stdc++.h>
#define INF 2000000000000000000
#define ll long long
#define pll pair<ll, ll>
using namespace std;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  string S;
  cin >> S;
  string ans;
  for (ll i = 0; i < S.size(); ++i) {
    if (S.at(i) >= 'a') {
      ans += (char)(S.at(i) - 'a' + 'A');
    }
    else {
      ans += (char)(S.at(i) - 'A' + 'a');
    }
  }
  cout << ans << "\n";
}