#include <iostream>
#include <string>
using namespace std;

int main(int argc, char**argv)
{
	string s; cin >> s;
	int sub = ('a'-'A');
	for (int ii=0; ii<s.size(); ++ii) {
		s[ii] = islower(s[ii]) ? toupper(s[ii]) : tolower(s[ii]);
	}
	cout << s << endl;
	return 0;
}