Neko loves divisors. During the latest number theory lesson, he got an interesting exercise from his math teacher.

Neko has two integers a and b. His goal is to find a non-negative integer k such that the least common multiple of a+k and b+k is the smallest possible. If there are multiple optimal integers k, he needs to choose the smallest one.

Given his mathematical talent, Neko had no trouble getting Wrong Answer on this problem. Can you help him solve it?

Input

The only line contains two integers a and b (1 ≤ a, b ≤ 10^9).

Output

Print the smallest non-negative integer k (k ≥ 0) such that the lowest common multiple of a+k and b+k is the smallest possible.

If there are many possible integers k giving the same value of the least common multiple, print the smallest one.

Examples

Input


6 10


Output


2

Input


21 31


Output


9

Input


5 10


Output


0

Note

In the first test, one should choose k = 2, as the least common multiple of 6 + 2 and 10 + 2 is 24, which is the smallest least common multiple possible.
import java.io.*;
import java.util.*;
import java.util.Queue;
import java.util.LinkedList;
import java.util.Stack;

public class Main
{
    @SuppressWarnings("unchecked")
     public static void main(String args[])throws IOException
    {
        Reader ob=new Reader();
        Writer out=new Writer(System.out);
        long a=ob.nL(),b=ob.nL();
        if(a>b)
        a=a^b^(b=a);
        long c=b-a;
        long min=(long)1e18;
        long k=0;
        for(int i=1;i*i<=c;i++)
    {
        long t=c/i;
        if(c%i==0)
        {
            long v=(long)(Math.ceil(1.0*a/i));
            v=v*i;
                long k1=v-a;
                long lcm=((a+k1)*(k1+b))/gcd(a+k1,b+k1);
                if(min>lcm&&k1>=0)
                {
                    k=k1;
                    min=lcm;
                }
               
           v=(long)(Math.ceil(1.0*a/t));
           v*=t;
               k1=v-a;
                lcm=((a+k1)*(k1+b))/gcd(a+k1,b+k1);
                if(min>lcm&&k1>=0)
                {
                    k=k1;
                    min=lcm;
                }  
            }
    }
    out.pln(k);
    out.flush();
}

static long inverse(long x, long p)
    {
        return pow(x, p - 2, p);
    }
static boolean isPrime(long n)
{
    long h=(long)Math.sqrt(n);
    for(long i=2;i<=h;i++)
    if(n%i==0)
    return false;
    return true&&n!=1;
}
    static long gcd(long a,long b)
    {
        if(a<b)
        return gcd(b,a);
        else if(b==0)
        return a;
        else
        return gcd(b,a%b);
    }
    static long pow(long a,long b,long mod){
		if(b == 0)	return 1;
		long t = pow(a,b>>1,mod);
		t = (t * t) % mod;
		if((b & 1) == 1)	t = (t * a);
		if(t >= mod)	t %= mod;
		return t;
}
    static long pow(long a,long b){
		if(b == 0)	return 1;
		long t = pow(a,b>>1);
		t = (t * t);
		if((b & 1) == 1)	t = (t * a);
		return t;
}
    static void seive(int n,int prime[])//1 for prime -1 for not prime
    {
        for(int i=2;i<=n;i++)
            if(prime[i]==0)
            {
                prime[i]=1;
                for(int j=2;j*i<=n;j++)
                prime[j*i]=-1;
            }
    }
    static int max(int ...a)
    {
        int m=a[0];
        for(int i=0;i<a.length;i++)
        m=Math.max(m,a[i]);
        return m;
        
    }
    static long max(long ...a)
    {
        long m=a[0];
        for(int i=0;i<a.length;i++)
        m=Math.max(m,a[i]);
        return m;
    }
    static int min(int ...a)
    {
        int m=a[0];
        for(int i=0;i<a.length;i++)
        m=Math.min(m,a[i]);
        return m;
    }
    static long min(long ...a)
    {
        long m=a[0];
        for(int i=0;i<a.length;i++)
        m=Math.min(m,a[i]);
        return m;
    }
    static class Pair<T1,T2>
    {
        T1 x;T2 y;
        Pair(T1 xx,T2 yy)
        {
            x=xx;
            y=yy;
        }
    }
    
	static class Writer {
		private final PrintWriter p;
		Writer(OutputStream o) {
			p = new PrintWriter(new BufferedWriter(new OutputStreamWriter(o)));
		}
		void p(Object... o1) {
			for (Object o11 : o1) {
				p.print(o11 + "" );
			}
		}
		void p(String s) {
			p.print(s);
		}
		void pln(Object... o1) {
			p(o1);
			p.println();
		}
		void flush() {
			p.flush();
		}
		void close() {
			p.close();
		}
	}
    static class Reader {
		private byte[] buf = new byte[1024];
		private int curChar;
		private int snumChars;
		int flag=0;
		FileReader file;
		Reader()
		{
		  }
		  Reader(String x)throws IOException
		  {
		      flag=1;
		      file=new FileReader(x);
		  }
		public int read() {
			if (snumChars == -1)
				throw new InputMismatchException();
			if (curChar >= snumChars) {
				curChar = 0;
				try {
					snumChars = System.in.read(buf);
				
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (snumChars <= 0)
					return -1;
			}
			return buf[curChar++];
		}
		public String nl() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isEndOfLine(c));
			return res.toString();
		}
		public String n() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isSpaceChar(c));
			return res.toString();
		}
		public long nL() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			long res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
		public int nI() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
		public int[] NIA(int n) //nextINtArray
		{
			int[] arr = new int[n];
			for (int i = 0; i < n; i++) {
				arr[i] = nI();
			}
			return arr;
		}
		public int[] NIA1(int n) //nextINtArray
		{
			int[] arr = new int[n+1];
			for (int i = 1; i <=n; i++) {
				arr[i] = nI();
			}
			return arr;
		}
		
		public long[] NLA(int n) //nextLongArray
		{
			long[] arr = new long[n];
			for (int i = 0; i < n; i++) {
				arr[i] = nL();
			}
			return arr;
}
		public long[] NLA1(int n) //nextLongArray
		{
			long[] arr = new long[n+1];
			for (int i = 1; i <=n; i++) {
				arr[i] = nL();
			}
			return arr;
}
		private boolean isSpaceChar(int c) {
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
		private boolean isEndOfLine(int c) {
			return c == '\n' || c == '\r' || c == -1;
		}
	}
static class DisJoint
{
    int a[],size[];
    DisJoint(int n)
    {
        a=new int[n+1];
        size=new int[n+1];
        for(int i=1;i<=n;i++)
    {
        a[i]=i;
        size[i]=1;
    }
    }
    int find(int n)
    {
        while(a[n]==n)
        {
            a[n]=a[a[n]];
        n=a[n];
    }
        return n;
    }
    void union(int a1,int b)
    {
        int x=find(a1);
        int y=find(b);
        if(size[x]>size[y])
    {
        a[y]=x;
        size[x]+=size[y];
    }
    else
    {
       a[x]=y;
       size[y]+=size[x];
    }
        //System.out.println(Arrays.toString(a));
    }
}
class Segment
{
    int sum[];
    void build(int a[],int v,int l,int r)
    {
        if(l==r)
        sum[v]=a[l];
        else
        {
            int m=(l+r)/2;
            build(a,v*2,l,m);
            build(a,2*v+1,m+1,r);
            sum[v]=sum[v*2]+sum[2*v+1];
        }
    }
    void update(int a[],int l,int r,int x,int v,int y)
    {
        if(l==r&&r==y)
            sum[v]+=x;
        else if(l>y||y>r)
        return;
        else
        {
            int m=(l+r)/2;
            update(a,l,m,x,2*v,y);
            update(a,m+1,r,x,2*v+1,y);
            sum[v]=sum[2*v]+sum[2*v+1];
        }
    }
    int query(int v,int l,int r,int x,int y)
    {
        if(x>r||y<l)
        return 0;
        else if(x<=l&&r<=y)
        return sum[v];
        else
        {
            int m=(l+r)/2;
        return query(2*v,l,m,x,y)+query(2*v+1,m+1,r,x,y);  
    }
}
}

static class Trie
  {
      Trie child[]=new Trie[26];
      int count=0;
    }
   /* void insert(String a)
    {
        Trie tmp=root;
        for(int i=0;i<a.length();i++)
        {
            int v=a.charAt(i)-'a';
            if(tmp.child[v]==null)
            {
                tmp.child[v]=new Trie();
                
            }
                tmp=tmp.child[v];
            }
            if(tmp.count==0)
            r++;
            tmp.count=1;
        }*/
    }
    