Impact factor of a scientific journal is a measure reflecting the average number of citations to articles published in science journals. For this task we are using a simplified formula for calculating the impact factor:

**Rounding is always performed up.** For example the impact factor of the "Journal for ore research and time wasting" that published articles quoted times is rounding up to .

You are the editor of one scientific journal. You know how many articles you are going to publish and the owners are pushing you to reach a specific impact factor. You are wondering how many scientists you will have to bribe to cite your article to meet the owners' demands. Since money is tight you want to bribe the **minimal** amount of scientists.

#### Input

First and only line of input will contain integers, , number of articles you plan to publish and impact factor the owners require.

#### Output

First and only line of output should contain one integer, the **minimal** number of scientists you need to bribe.

#### Sample Input 1

`38 24`

#### Sample Output 1

`875`

#### Sample Input 2

`1 100`

#### Sample Output 2

`100`

#### Sample Input 3

`10 10`

#### Sample Output 3

`91`

## Comments