#include<bits/stdc++.h>
#define rep(i,a,n) for (int i = a;i < n;i++)
#define per(i,n,a) for (int i = n-1;i >= a;i--)
using namespace std;

int main() {
    string s, ans;
    cin >> s;
    rep(i, 0, s.size()) {
        if (s[i] >= 'a' && s[i] <= 'z') {
            ans = s[i] - 32;
            cout << ans;
        }else{
            ans = s[i] + 32;
            cout << ans;
        }
    }
    cout << "\n";
}