#include<iostream>
using namespace std;
int common_father(int x,int y){
    if(x==y){
        return x;
    }
    else if(x>y){
        return common_father(x/2,y);
    }
    else{
        return common_father(x,y/2);
    }
}
int main(){
    int x,y;
    while(cin>>x>>y){
        cout<<common_father(x,y)<<endl;
    }
}