You are given two natural numbers ** A** and

**. Determine the positive natural number**

`B`**such that the least common multiple of the numbers**

`N`**and**

`A + N`**is minimal.**

`B + N`### Input

The only line of the input contains two natural numbers: ** A** and

**. None of them is exceeding**

`B`**.**

`10`^{9}### Output

Output the positive natural number ** N** such that

**is minimal. If there are several values of**

`LCM(A + N, B + N)`**which yield the minimum, output the smallest one.**

`N`### Sample

Input | Output |
---|---|

4 10 | 2 |