#include<iostream>
#include<string>

using namespace std;

int main(){

	string s;
	
	cin>>s;

	for(int i=0;i<s.size();i++){
		if(s[i]>='a'&&s[i]<='z') cout<<(char)(s[i]-'a'+'A');
		else cout<<(char)(s[i]-'A'+'a');
	}
	cout<<endl;
}