char

#include<bits/stdc++.h>//submitRecord//
using namespace std;
//const int N=1e7+10;
int main(){
//freopen("","r",stdin);
//freopen("","w",stdout);
ios::sync_with_stdio();
cin.tie(nullptr);
cout.tie(nullptr);
char s;
cin>>s;
if(s>='A'&&s<='Z'){
s=s+32;
cout<<s;
}else if(s>='a'&&s<='z'){
s=s-32;
cout<<s;
}
//fclose(stdin);
//fclose(stdout);
return 0;
}