#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>

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

	int n = strlen(s);

	char* a;
	a = (char*)malloc(sizeof(char) * n);

	for (int i = 0; i < n; i++)
	{
		if (0x41 <= s[i] && s[i] <= 0x5a)
		{
			a[i] = tolower(s[i]);
		}
		else
		{
			a[i] = toupper(s[i]);
		}
	}

	for (int i = 0; i < n; i++)
	{
		printf("%c", a[i]);
	}

	return 0;
}