#include<iostream>
using namespace std;
int main()
{
	int n,r;
	cout<<"n="; cin>>n;
	r=0;
	while(n>0)
	{
		if(n%10%2!=0) r=r*10+n%10;
		n=n/10;
	}
	
	while(r>0)
	{
		n=n*10+r%10;
		r=r/10;
	}
	cout<<n;
}