Sum of Squares

Given a positive integer n, compute the sum of squares of the first n natural numbers. In other words, calculate

\( S = \frac{n(n+1)(2n+1)}{6} \)

and output the result.

inputFormat

The input consists of a single line containing one integer n (1 ≤ n ≤ 10⁵).

outputFormat

Output a single integer representing the sum of squares of the first n natural numbers.

sample

1

1