CF440B.Balancer

Petya has k matches, placed in n matchboxes lying in a line from left to right. We know that k is divisible by n. Petya wants all boxes to have the same number of matches inside. For that, he can move a match from its box to the adjacent one in one move. How many such moves does he need to achieve the desired configuration?

彼得有 $k$ 根火柴，放置在从左到右排成一行的 $n$ 个火柴盒中。已知 $k$ 能被 $n$ 整除。彼得希望每个盒子中的火柴数量都相同。为此，他每次可以将一根火柴从一个盒子移动到其相邻的盒子（左邻或右邻）。为达到目标状态，他最少需要多少次这样的移动？

The first line contains integer n (1 ≤ n ≤ 50000). The second line contains n non-negative numbers that do not exceed 109, the i-th written number is the number of matches in the i-th matchbox. It is guaranteed that the total number of matches is divisible by n.

第一行包含一个整数 $n$（$1 \leq n \leq 50000$）。第二行包含 $n$ 个非负整数，每个数都不超过 $10^9$；其中第 $i$ 个数表示第 $i$ 个火柴盒中的火柴数量。保证火柴总数能被 $n$ 整除。

Print the total minimum number of moves.

输出所需的最少总步数。