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

int main(void){
	char *str = malloc(101);
	scanf("%s",str);
	int len = strlen(str);
	char *p = str;
	
	int ans = 0;
	for(int i = 0;i< len;i++){
		if((p[i] >= 'a') && (p[i] <= 'z')){
			str[i] = toupper(str[i]);
		}else{
			p[i] = tolower(p[i]);
		}
		printf("%s",p[i]);
	}
}