#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; ++i)
using ll = long long;
using namespace std;
const int INF = 1e9;
const int MOD = INF + 7;

int main() {
    string s;
    cin >> s;

    rep(i,s.size()){
        if(s[i]<'a')
            cout << char(s[i] + 'a' - 'A');
        else
            cout << char(s[i] + 'A' - 'a');
    }
    cout << endl;
    
    return 0;
}