Given a non-negative integer \(n\), compute

\(S(n) = 1^2 + 2^2 + \cdots + n^2\).

For \(n = 0\), define \(S(0) = 0\).

Input

One line containing \(n\).

The input satisfies:

• \(0 \le n \le 10^6\)
• The answer fits in a signed 64-bit integer.

Output

Print \(S(n)\).

Example

Input

3

Output

14