Given a non-empty integer array of size n, find the minimum number of moves required to make all array elements equal, where a move is incrementing n - 1 elements by 1.
Example:
Input:
[1,2,3]
Output:
3
Explanation:
Only three moves are needed (remember each move increments two elements):
[1,2,3] => [2,3,3] => [3,4,3] => [4,4,4]
n = len(nums)
经过 m 次移动后，每个数字都是 x，可得
sum + m * (n - 1) = x * n
实际上，每次移动都会往最小的数字 min 上加一，所以
x = min + m
通过以上两个等式，可得
m = sum - min * n