22101 - 判断并转换字符

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