#include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
using namespace std;

int main() {
	string S;
	cin>>S;
	string L("ABCDEFGHIJKLMNOPQRSTUVWXYZ");
	string s("abcdefghijklmnopqrstuvwxyz");
	
	for(int i=0;i<S.size();i++){
		for(int j=0;j<L.size();j++){
			if(S[i]==L[j]){
				S[i]=s[j];
				break;
			}else if(S[i]==s[j]){
				S[i]=L[j];
				break;
			}
		}
		cout<<S[i];
	}
	
	cout<<endl;
	return 0;
}