#include <stdio.h>
int main()
{
char ch1,ch2;
scanf("%c%c",&ch1,&ch2);
if(ch1>='a'&&ch1<='z')
ch1-=32;
else if(ch1>='A'&&ch1<='Z')
ch1+=32;
if(ch2>='a'&&ch1<='z')
ch2-=32;
else if(ch2>='A'&&ch1<='Z')
ch2+=32;
printf("%c %c",ch1,ch2);
return 0;
}
//运行示例: