#include <bits/stdc++.h>

using namespace std;

int main(int argc, char **argv) {
	char buf[101];
	fgets(buf, sizeof(buf), stdin);

	char pass[101];
	sscanf(buf, "%s", pass);

	for (int i = 0; i < strlen(pass); i++) {
		if (pass[i] <= 'Z') {
			printf("%c", pass[i] - 'A' + 'a');
		} else {
			printf("%c", pass[i] - 'a' + 'A');
		}
	}
	printf("\n");
	return 0;
}