Project Euler #53: Combinatoric selections

_{This problem is a programming version of Problem 53 from projecteuler.net}

There are exactly ten ways of selecting three from five, :

In combinatorics, we use the notation,

In general,

It is not until , that a value exceeds one-million:

How many, not necessarily distinct, values of , for , are greater than K?

Input Format

Input contains two integers and .

Constraints

Output Format

Print the answer corresponding to the test case.

Sample Input

23 1000000

Sample Output