Competitions
DSA Week 1
Function-10
The function is given with nonnegative integer arguments m and n (m ≤ n):
Find the value of the function.
Input data
Two nonnegative integers n and m (0 ≤ n, m ≤ 20).
Output data
Print the value of the function f(m, n).
Examples
Input example #1
4 2
Output example #1
6