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.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.*;

public class CFCR1152 {
    public static void main(String[] args) throws Exception {
        boolean local = System.getProperty("ONLINE_JUDGE") == null;
        boolean async = false;

        Charset charset = Charset.forName("ascii");

        FastIO io = local ? new FastIO(new FileInputStream("D:\\DATABASE\\TESTCASE\\Code.in"), System.out, charset) : new FastIO(System.in, System.out, charset);
        Task task = new Task(io, new Debug(local));

        if (async) {
            Thread t = new Thread(null, task, "dalt", 1 << 27);
            t.setPriority(Thread.MAX_PRIORITY);
            t.start();
            t.join();
        } else {
            task.run();
        }

        if (local) {
            io.cache.append("\n\n--memory -- \n" + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) >> 20) + "M");
        }

        io.flush();
    }

    public static class Task implements Runnable {
        final FastIO io;
        final Debug debug;
        int inf = (int) 1e8;

        public Task(FastIO io, Debug debug) {
            this.io = io;
            this.debug = debug;
        }

        @Override
        public void run() {
            solve();
        }

        public void solve() {
            int a = io.readInt();
            int b = io.readInt();
            if (a < b) {
                int t = a;
                a = b;
                b = t;
            }

            if (a == b) {
                io.cache.append(0);
                return;
            }

            int d = a - b;
            long minLcm = (long)a * b / Mathematics.gcd(a, b);
            int minK = 0;
            for (int i = 1; i * i <= d; i++) {
                if (d % i != 0) {
                    continue;
                }
                int j = d / i;
                {
                    int k = (j - b % j) % j;
                    long lcm = (long) (a + k) * (b + k) / Mathematics.gcd(a + k, b + k);
                    if (lcm < minLcm) {
                        minLcm = lcm;
                        minK = k;
                    } else if (lcm == minLcm && k < minK) {
                        minK = k;
                    }
                }

                {
                    int k = (i - b % i) % i;
                    long lcm = (long) (a + k) * (b + k) / Mathematics.gcd(a + k, b + k);
                    if (lcm < minLcm) {
                        minLcm = lcm;
                        minK = k;
                    } else if (lcm == minLcm && k < minK) {
                        minK = k;
                    }
                }
            }

            io.cache.append(minK);
        }

        public boolean isPow2(int x) {
            return (x & -x) == x;
        }
    }

    public static class Mathematics {

        public static int ceilPowerOf2(int x) {
            return 32 - Integer.numberOfLeadingZeros(x - 1);
        }

        public static int floorPowerOf2(int x) {
            return 31 - Integer.numberOfLeadingZeros(x);
        }

        public static long modmul(long a, long b, long mod) {
            return b == 0 ? 0 : ((modmul(a, b >> 1, mod) << 1) % mod + a * (b & 1)) % mod;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static int gcd(int a, int b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static int gcd0(int a, int b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static int extgcd(int a, int b, int[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                int g = extgcd0(b, a, coe);
                int tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static int extgcd0(int a, int b, int[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            int g = extgcd0(b, a % b, coe);
            int n = coe[0];
            int m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get the greatest common divisor of a and b
         */
        public static long gcd(long a, long b) {
            return a >= b ? gcd0(a, b) : gcd0(b, a);
        }

        private static long gcd0(long a, long b) {
            return b == 0 ? a : gcd0(b, a % b);
        }

        public static long extgcd(long a, long b, long[] coe) {
            if (a >= b) {
                return extgcd0(a, b, coe);
            } else {
                long g = extgcd0(b, a, coe);
                long tmp = coe[0];
                coe[0] = coe[1];
                coe[1] = tmp;
                return g;
            }
        }

        private static long extgcd0(long a, long b, long[] coe) {
            if (b == 0) {
                coe[0] = 1;
                coe[1] = 0;
                return a;
            }
            long g = extgcd0(b, a % b, coe);
            long n = coe[0];
            long m = coe[1];
            coe[0] = m;
            coe[1] = n - m * (a / b);
            return g;
        }

        /**
         * Get y where x * y = 1 (% mod)
         */
        public static int inverse(int x, int mod) {
            return pow(x, mod - 2, mod);
        }

        /**
         * Get x^n(% mod)
         */
        public static int pow(int x, int n, int mod) {
            n = mod(n, mod - 1);
            x = mod(x, mod);
            int bit = 31 - Integer.numberOfLeadingZeros(n);
            long product = 1;
            for (; bit >= 0; bit--) {
                product = product * product % mod;
                if (((1 << bit) & n) != 0) {
                    product = product * x % mod;
                }
            }
            return (int) product;
        }

        public static long longpow(long x, long n, long mod) {
            if (n == 0) {
                return 1;
            }
            long prod = longpow(x, n >> 1, mod);
            prod = modmul(prod, prod, mod);
            if ((n & 1) == 1) {
                prod = modmul(prod, x, mod);
            }
            return prod;
        }

        /**
         * Get x % mod
         */
        public static int mod(int x, int mod) {
            return x >= 0 ? x % mod : (((x % mod) + mod) % mod);
        }

        /**
         * Get n!/(n-m)!
         */
        public static long permute(int n, int m) {
            return m == 0 ? 1 : n * permute(n - 1, m - 1);
        }

        /**
         * Put all primes less or equal to limit into primes after offset
         */
        public static int eulerSieve(int limit, int[] primes, int offset) {
            boolean[] isComp = new boolean[limit + 1];
            int wpos = offset;
            for (int i = 2; i <= limit; i++) {
                if (!isComp[i]) {
                    primes[wpos++] = i;
                }
                for (int j = offset, until = limit / i; j < wpos && primes[j] <= until; j++) {
                    int pi = primes[j] * i;
                    isComp[pi] = true;
                    if (i % primes[j] == 0) {
                        break;
                    }
                }
            }
            return wpos - offset;
        }

        /**
         * Round x into integer
         */
        public static int intRound(double x) {
            if (x < 0) {
                return -(int) (-x + 0.5);
            }
            return (int) (x + 0.5);
        }

        /**
         * Round x into long
         */
        public static long longRound(double x) {
            if (x < 0) {
                return -(long) (-x + 0.5);
            }
            return (long) (x + 0.5);
        }
    }

    public static class FastIO {
        public final StringBuilder cache = new StringBuilder();
        private final InputStream is;
        private final OutputStream os;
        private final Charset charset;
        private StringBuilder defaultStringBuf = new StringBuilder(1 << 8);
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastIO(InputStream is, OutputStream os, Charset charset) {
            this.is = is;
            this.os = os;
            this.charset = charset;
        }

        public FastIO(InputStream is, OutputStream os) {
            this(is, os, Charset.forName("ascii"));
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public long readLong() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            long val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

        public double readDouble() {
            boolean sign = true;
            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+';
                next = read();
            }

            long val = 0;
            while (next >= '0' && next <= '9') {
                val = val * 10 + next - '0';
                next = read();
            }
            if (next != '.') {
                return sign ? val : -val;
            }
            next = read();
            long radix = 1;
            long point = 0;
            while (next >= '0' && next <= '9') {
                point = point * 10 + next - '0';
                radix = radix * 10;
                next = read();
            }
            double result = val + (double) point / radix;
            return sign ? result : -result;
        }

        public String readString(StringBuilder builder) {
            skipBlank();

            while (next > 32) {
                builder.append((char) next);
                next = read();
            }

            return builder.toString();
        }

        public String readString() {
            defaultStringBuf.setLength(0);
            return readString(defaultStringBuf);
        }

        public int readLine(char[] data, int offset) {
            int originalOffset = offset;
            while (next != -1 && next != '\n') {
                data[offset++] = (char) next;
                next = read();
            }
            return offset - originalOffset;
        }

        public int readString(char[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (char) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public int readString(byte[] data, int offset) {
            skipBlank();

            int originalOffset = offset;
            while (next > 32) {
                data[offset++] = (byte) next;
                next = read();
            }

            return offset - originalOffset;
        }

        public char readChar() {
            skipBlank();
            char c = (char) next;
            next = read();
            return c;
        }

        public void flush() {
            try {
                os.write(cache.toString().getBytes(charset));
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        public boolean hasMore() {
            skipBlank();
            return next != -1;
        }
    }

    public static class Debug {
        private boolean allowDebug;

        public Debug(boolean allowDebug) {
            this.allowDebug = allowDebug;
        }

        public void assertTrue(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (!flag) {
                fail();
            }
        }

        public void fail() {
            throw new RuntimeException();
        }

        public void assertFalse(boolean flag) {
            if (!allowDebug) {
                return;
            }
            if (flag) {
                fail();
            }
        }

        private void outputName(String name) {
            System.out.print(name + " = ");
        }

        public void debug(String name, int x) {
            if (!allowDebug) {
                return;
            }

            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, long x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, double x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, int[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, long[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, double[] x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.toString(x));
        }

        public void debug(String name, Object x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println("" + x);
        }

        public void debug(String name, Object... x) {
            if (!allowDebug) {
                return;
            }
            outputName(name);
            System.out.println(Arrays.deepToString(x));
        }
    }
}
