#include <iostream>
#include <vector>
#include <algorithm>
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;
}