#include <stdio.h>
#include <algorithm>
#include <deque>
using namespace std;
using ll = long long;

//164
int main() {
	char s[101];
	scanf("%s", s);

	for (int i = 0; s[i] != 0; i++) {
		if ('a' <= s[i] && s[i] <= 'z')
			s[i] = 'A' + s[i] - 'a';
		else
			s[i] = 'a' + s[i] - 'A';
	}
	printf("%s\n", s);
}