max-diff.js

//2016. Maximum Difference Between Increasing Elements

// Given a 0-indexed integer array nums of size n, find the maximum difference between nums[i] and nums[j] (i.e., nums[j] - nums[i]), such that 0 <= i < j < n and nums[i] < nums[j].

// Return the maximum difference. If no such i and j exists, return -1.

 

// Example 1:

// Input: nums = [7,1,5,4]
// Output: 4
// Explanation:
// The maximum difference occurs with i = 1 and j = 2, nums[j] - nums[i] = 5 - 1 = 4.
// Note that with i = 1 and j = 0, the difference nums[j] - nums[i] = 7 - 1 = 6, but i > j, so it is not valid.
// Example 2:

// Input: nums = [9,4,3,2]
// Output: -1
// Explanation:
// There is no i and j such that i < j and nums[i] < nums[j].
// Example 3:

// Input: nums = [1,5,2,10]
// Output: 9
// Explanation:
// The maximum difference occurs with i = 0 and j = 3, nums[j] - nums[i] = 10 - 1 = 9.

var maximumDifference = function(nums) {
    //     left is index i
    //     right is index j
        let left = 0
        let right = 1
        let maxDiff = -1
        while(right <= nums.length-1){
            if(nums[left] < nums[right]){
                maxDiff = (nums[right]- nums[left]) > maxDiff?
                nums[right] - nums[left] 
                : maxDiff
            }else{
                left = right
            }
            right++
        }
        return maxDiff
};