LeetCode 453. Minimum Moves to Equal Array Elements

原题链接在这里：https://leetcode.com/problems/minimum-moves-to-equal-array-elements/

题目：

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]

题解：

Think on the other way, increasing n - 1 elements == decreasing 1 element.

Decrease all num to min(nums).

Time Complexity: O(n). n = nums.length.

Space: O(1).

AC Java:

public class Solution {
    public int minMoves(int[] nums) {
        int min = Integer.MAX_VALUE;
        for(int num : nums){
            min = Math.min(min, num);
        }
        
        int moves = 0;
        for(int num: nums){
            moves += (num - min);
        }
        return moves;
    }
}

Could be one pass.

Time Complexity: O(n).

Space: O(1).

AC Java:

class Solution {
    public int minMoves(int[] nums) {
        if(nums == null || nums.length < 2){
            return 0;
        }
        
        int min = Integer.MAX_VALUE;
        int sum = 0;
        for(int num : nums){
            min = Math.min(min, num);
            sum += num;
        }
        
        return sum - min * nums.length;
    }
}

跟上Minimum Moves to Equal Array Elements II.