#include <bits/stdc++.h>

using namespace std;

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

    string s,s2;
    cin >> s;
    const char* p = s.c_str();

    for (size_t i=0; i<s.size();++i)
    {
        if (*p>='a')
            s2+=*p++ -'a'+'A';
        else
            s2+=*p++ +'a'-'A';
    }

	cout << s2 << "\n";

	return 0;
}