好吃的手撸头文件

#include<bits/stdc++.h>
using namespace std;
int main(){
char a;
cin>>a;
if(a>='a' and a<='z'){
a=a-32;
cout<<a;
}
else if(a>='A' and a<='Z'){
a=a+32;
cout<<a;
}
return 0;
}