简单！

#include<bits/stdc++.h>
#define int long long
using namespace std;
int x,y,q,a,b,c[10000005],t1;
signed main(){
	cin>>x>>y>>q;
    for(int i=2;i<=sqrt(x);i++){
        if(x%i==0){
            if(y%i==0)c[++t1]=i;
            if(y%(x/i)==0)c[++t1]=x/i;
        }
    }
    sort(c+1,c+1+t1,greater<int>());
	while(q--){
        cin>>a>>b;
        int f=0;
        for(int i=1;i<=t1;i++){
            if(c[i]>=a&&c[i]<=b){
                cout<<c[i]<<"\n";
                f=1;
                break;
            }
        if(c[i]<a)break;
        }
        if(f==0)cout<<"-1"<<"\n";
    }
	return 0;
}