#include<stdio.h>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
#include <sstream>
#include <iostream>
#include <string>
#include <stdio.h>

using namespace std;

int main() {

	string S;
	cin >> S;

	for (int i = 0; i<S.size(); i++) {
		if(S[i] < 'a') cout << (char)(S[i] + ('a' - 'A'));
		else cout << (char)(S[i] - ('a' - 'A'));
	}
	cout << endl;

	return 0;
}