信奥赛一本通1223 An Easy Problem

#include<bits/stdc++.h>
using namespace std;

int x,k;

int main(){
	
	while(cin>>x,x){
		int tmp=0,cnt=0;
		
		while(k=x&-x,x-=k,x&(k<<1)){
			tmp|=1<<cnt++;
		}
		
		cout<<(x|k<<1|tmp)<<endl;
	}
	return 0;
}