Sum of 25 Consecutive Integers

Given a positive integer n, your task is to compute the sum of 25 consecutive integers starting from n:

$$n + (n+1) + (n+2) + \cdots + (n+24)$$

This can be computed using the arithmetic series formula. Note that the sum of the first 25 consecutive integers starting from n is:

$$25n + \frac{24 \times 25}{2} = 25n + 300.$$

inputFormat

The input consists of a single positive integer n (for example, \(1 \le n \le 10^9\)).

outputFormat

Output a single integer which is the sum of 25 consecutive numbers starting from n.

sample

1

325