Valid Word Combinations

You are given two integers N and L. An alphabet of N distinct characters is available, and you need to form words of length L under the constraint that the characters in the word must be in strictly increasing order (based on their given ranking).

This means that each valid word corresponds to a combination of L characters chosen from N, and the total number is given by the binomial coefficient:

\( \binom{N}{L} \)

Your task is to compute \( \binom{N}{L} \) for the given values of N and L.

inputFormat

The input is provided via stdin and consists of a single line containing two space-separated integers N and L.

outputFormat

The output should be printed to stdout as a single integer which is the number of valid words, i.e., the binomial coefficient \( \binom{N}{L} \).

4 2

6