#include <iostream>
using namespace std;

string f(const string& a){
    string res;
      for (char c : a) {
            if (islower(c)) {
                res += toupper(c);
            } else if (isupper(c)) {
                res += tolower(c);
            } else {
                res += c;
            }
        }
        return res;
    }

int main(){
    string s;
    cin >> s;
    cout << f(s) << endl;
}