#include<iostream>
#include<cstring>
using namespace std;
int main(){
    string s,b;
    getline(cin,s);
    for(int i=0;i<s.size();i++){

    if(i<=s.size()-2)b+=s[i]+s[i+1];
    else b+=s[0]+s[i];
}
cout<<b;

}