1464. Maximum Product of Two Elements in an Array

QUESTION:

Given the array of integers nums, you will choose two different indices i and j of that array. Return the maximum value of (nums[i]-1)*(nums[j]-1).

Example 1:

Input: nums = [3,4,5,2]
Output: 12 
Explanation: If you choose the indices i=1 and j=2 (indexed from 0), you will get the maximum value, that is, (nums[1]-1)*(nums[2]-1) = (4-1)*(5-1) = 3*4 = 12. 

Example 2:

Input: nums = [1,5,4,5]
Output: 16
Explanation: Choosing the indices i=1 and j=3 (indexed from 0), you will get the maximum value of (5-1)*(5-1) = 16.

Example 3:

Input: nums = [3,7]
Output: 12
 

Constraints:

2 <= nums.length <= 500
1 <= nums[i] <= 10^3

EXPLANATION:

题目比较简单,思路:

  1. 找到最大值
  2. 找到第二大的值
  3. 将两者相乘

至于如何找到最大和第二大的值,可以直接排序,也可以采用for循环的方式。

SOLUTION:

class Solution {
    public int maxProduct(int[] nums) {
        Arrays.sort(nums);
        return (nums[nums.length-1]-1)*(nums[nums.length-2]-1);
    }
}