#include<iostream>
#include<string>
#include<fstream>
#include<iomanip>
#include<vector>
#include<cctype>
#include<algorithm>
using namespace std;

int main()
{
	string s, t;
	cin >> s;
	for (int i = 0; i < static_cast<int>(s.size()); i++)
	{
		if (islower(s[i]))t += toupper(s[i]);
		else t += tolower(s[i]);
	}
	cout << t << endl;
	return 0;
}