Leetcode-Candy

There are N children standing in a line. Each child is assigned a rating value.

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.

What is the minimum candies you must give?

Solution:

public class Solution {
    public int candy(int[] ratings) {
        int[] num = new int[ratings.length];
        Arrays.fill(num,1);
        for (int i=1;i<ratings.length;i++)
            if (ratings[i]>ratings[i-1]) num[i] = num[i-1]+1;
 
        for (int i=ratings.length-2;i>=0;i--)
            if (ratings[i]>ratings[i+1] && num[i]<=num[i+1]) 
                num[i] = num[i+1]+1;

        int sum = 0;
        for (int i=0;i<ratings.length;i++) sum += num[i];

        return sum;        
    }
}