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

int main(void){
//入力された文字列を格納する変数
char Fpassword[100] = {};
char Tpassword[100] = {};
int i,j;
//入力待ち
scanf("%s",Fpassword);

for(i = 0;i<100;i++){
	if(isupper(Fpassword[i]) == 0){
		Tpassword[i] = toupper(Fpassword[i]);
	}else{
		Tpassword[i] = tolower(Fpassword[i]);
	}

}

for(j = 0;j < 100;j++){
	if(Tpassword[j] != '\0'){
		printf("%c",Tpassword[j]);
	}
}
	printf("\n");




return 0;
}