using System;
using System.Collections;
using System.Collections.Generic;
 
class TEST{
	static void Main(){
		Sol mySol =new Sol();
		mySol.Solve();
	}
}

class Sol{
	public void Solve(){
		
		List<long> L=new List<long>();
		int[] ord0=new int[6]{0,0,1,1,2,2};
		int[] ord1=new int[6]{1,2,0,2,0,1};
		int[] ord2=new int[6]{2,1,2,0,1,0};
		
		for(int t=0;t<6;t++){
			long lcm=Y[ord0[t]]*Y[ord1[t]]/gcd(Y[ord0[t]],Y[ord1[t]]);
			long tmp=-1;
			for(long x=X[ord0[t]];x<=lcm*2;x+=Y[ord0[t]]){
				if(x%Y[ord1[t]]==X[ord1[t]]){if(x!=0)tmp=x;break;}
			}
			
			if(tmp==-1){
				L.Add(-1);
				continue;;
			}
			
			long lcm2=lcm*Y[ord2[t]]/gcd(lcm,Y[ord2[t]]);
			long ans=-1;
			for(long x=tmp;x<=lcm2*2;x+=lcm){
				if(x%Y[ord2[t]]==X[ord2[t]]){if(x!=0)ans=x;break;}
			}
			L.Add(ans);
		}
		L.Sort();
		
		int ptr=0;while(ptr<6&&L[ptr]==-1)ptr++;
		Console.WriteLine(ptr==6?-1:L[ptr]);
		
		
	}
	
	
	
	long[] X,Y;
	public Sol(){
		X=new long[3];
		Y=new long[3];
		for(int i=0;i<3;i++){
			var d=rla();
			X[i]=d[0];Y[i]=d[1];
		}
	}
	long gcd(long a,long b){
		return a==0?b:gcd(b%a,a);
	}



	static String rs(){return Console.ReadLine();}
	static int ri(){return int.Parse(Console.ReadLine());}
	static long rl(){return long.Parse(Console.ReadLine());}
	static double rd(){return double.Parse(Console.ReadLine());}
	static String[] rsa(){return Console.ReadLine().Split(' ');}
	static int[] ria(){return Array.ConvertAll(Console.ReadLine().Split(' '),e=>int.Parse(e));}
	static long[] rla(){return Array.ConvertAll(Console.ReadLine().Split(' '),e=>long.Parse(e));}
	static double[] rda(){return Array.ConvertAll(Console.ReadLine().Split(' '),e=>double.Parse(e));}
}