CF220E Little Elephant and Inversions

The Little Elephant has array $ a $ , consisting of $ n $ positive integers, indexed from 1 to $ n $ . Let's denote the number with index $ i $ as $ a_{i} $ . The Little Elephant wants to count, how many pairs of integers $ l $ and $ r $ are there, such that $ 1

The first line contains two integers $ n $ and $ k $ $ (2

In a single line print a single number — the answer to the problem.