Candy

Problem statement

There are n children standing in a line. Each child is assigned a rating value given in the integer array ratings.

You are giving candies to these children subjected to the following requirements:

• Each child must have at least one candy.
• Children with a higher rating get more candies than their neighbors.

Return the minimum number of candies you need to have to distribute the candies to the children.

Example 1:

Input: ratings = [1,0,2]Output: 5Explanation: You can allocate to the first, second and third child with 2, 1, 2 candies respectively.

Example 2:

Input: ratings = [1,2,2]Output: 4Explanation: You can allocate to the first, second and third child with 1, 2, 1 candies respectively.The third child gets 1 candy because it satisfies the above two conditions.

Constraints:

• n == ratings.length
• 1 <= n <= 2 * 104
• 0 <= ratings[i] <= 2 * 104

My solution

/**
 * @param {number[]} ratings
 * @return {number}
 */
var candy = function(ratings) {
    const leftStart = [];
    const rightStart = []
    
    leftStart[0] = 1;
    rightStart[ratings.length - 1] = 1;
    
    for (let i = 1; i < ratings.length; i++) {
        if (ratings[i] > ratings[i - 1]) {
            leftStart[i] = leftStart[i - 1] + 1
        } else {
            leftStart[i] = 1
        }
    }
    
    for (let i = ratings.length - 2; i >= 0; i--) {
        console.log(i)
        if (ratings[i] > ratings[i + 1]) {
            rightStart[i] = rightStart[i + 1] + 1
        } else {
            rightStart[i] = 1
        }
    }
    
    // console.log(leftStart)
    // console.log(rightStart)
    
    let total = 0;
    for (let i = 0; i < ratings.length; i++) {
        total += Math.max(leftStart[i], rightStart[i])
    }
    
    return total;
};