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

int main()
{
	string password, conv = "";

	cin >> password;

	for (int i = 0; i < password.size(); i++)
	{
		if (isupper(password[i]))
		{
			conv.push_back(tolower(password[i]));
		}
		else
		{
			conv.push_back(toupper(password[i]));
		}
	}
	cout << conv << endl;
}