#include <algorithm>
#include <iostream>
#include <string>

using namespace std;

static void setup()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
}

static void run()
{
    string s;
    cin >> s;

    transform(begin(s), end(s), begin(s), [](char c) {
        if (c >= 'a' && c <= 'z') {
            return 'A' + (c - 'a');
        }
        else {
            return 'a' + (c - 'A');
        }
    });

    cout << s << endl;
}

int main(int argc, char **argv)
{
    setup();
    run();
    return 0;
}