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


int main()
{
	string str,outstr;
	cin>>str;
	for (int i = 0; i < str.length(); ++i)
	{
		if(islower(str.at(i))){
			cout<<char(toupper(str.at(i)));
		}else{
			cout<<char(tolower(str.at(i)));
		}
	}
	cout<<endl;
	return 0;
}