#include <stdio.h>

int main(void)
{
    char s[101];
    int i = 0;
    
    fgets(s, 101, stdin);
    
    while(s[i] != '\0'){
        if((s[i] >= 'a') && (s[i] <= 'z')){
            s[i] = toupper(s[i]);
         }else{
            s[i] = tolower(s[i]);
         }
         i++;
    }
    
    printf("%s", s);
    
    return 0;
}