题解

#include<bits/stdc++.h>
using namespace std;
int main(){
char n;
cin >>n;
if(n>='a'&&n<='z')
{
n=n-32;
cout<<n;

}
else if(n>='A'&&n<='Z'){

    n=n+32;
    cout<<n;
    
}
else 
{
    cout <<"SORRY I DONOT KNOW WHAT IT IS";
}

return 0;
}