#include <iostream>
#include <string.h>
using namespace std;
int main()
{
char ch[100];
gets(ch);
int len=strlen(ch);
for(int i=0;i<len;i++)
{
if(ch[i]>='A' && ch[i]<='Z')
{ch[i]=ch[i]+32;}
else if(ch[i]>='a' && ch[i]<='z')
{ch[i]=ch[i]-32;}
cout<<ch[i];
}
return 0;
}