题解

#include <iostream>
using namespace std;
int main(){
	string a,b,c;
	cin>>a;	
	for(int i=0;i<a.size();i++){
		if(i%2==0){
			b+=a[i];
		}
		else{
			c+=a[i];	
		}	
	}
	if(b>c){
		b+=c;
		cout<<b;
	 } 
	else {
		c+=b;
		cout<<c;
	}
	return 0;
}