#include <bits/stdc++.h>
using namespace std;
using ill = int long long;
#define rep(i, n) for (ill i = 0; i < (n); i++)
#define all(s) s.begin(), s.end()
using inp = pair<int, int>;
using vecb = vector<bool>;
using vecb2 = vector<vecb>;

int main()
{
    string s;
    cin >> s;
    vector<char> ans;
    rep(i, (ill)s.size())
    {
        if (islower(s[i]))
        {
            char t = toupper(s[i]);
            ans.push_back(t);
        }
        else
        {
            char t = tolower(s[i]);
            ans.push_back(t);
        }
    }
    rep(i, (ill)ans.size())
    {
        cout << ans[i];
    }
}