#include <iostream>
#include <cstring>
using namespace std;


int main(){
//	freopen("text.txt","r",stdin);
	string s;
	while(cin>>s){
		for(int i=0;i<s.length();i++){
			if(i%2 == 0){
				if(s[i] < 95)
					cout<<s[i];
				else
					cout<<(char)(s[i]-'a'+'A');
			}
			else{
				if(s[i] > 95)
					cout<<s[i];
				else
					cout<<(char)(s[i]-'A'+'a');
			}
		}
		cout<<" ";
	}
	return 0;
}