Problem Statement

Given is a number sequence $A$ of length $N$. Find the sum of squared differences of every pair of elements: $\displaystyle \sum_{i = 2}^{N} \sum_{j = 1}^{i - 1} (A_i - A_j)^2$.

Constraints

• $2 \le N \le 3 \times 10^5$
• $|A_i| \le 200$
• All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 A_3 \cdots A_N

Output

Print the answer.