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?

 

有N个孩子站在一条线。分配给每个孩子一个评级的价值。

你把糖果给这些孩子受到以下需求:

每个孩子必须至少有一个糖果。

评级较高的孩子得到更多的糖果比他们的邻居。

什么是你必须给的最低糖果吗?

以上内容是用有道翻译进行翻译

解题思路：------------------------------------------

每个小孩先发一块糖，然后从左向右进行遍历，如果arr[i]>arr[i-1]，就在前一个人的糖的数目的基础上加1；

最后从右往左遍历，加上所有的糖(从右往左遍历是考虑到权值为：7 5 8 9 6 4 12)的情况

 

import java.util.*;
public class Solution {
    public int candy(int[] ratings) {
        if(ratings==null || ratings.length==0) {
            return 0;
        }
         
        int[] count = new int[ratings.length];
        //每个孩子初始都有一个糖果
        Arrays.fill(count,1);
        int sum = 0;
        for(int i=1;i<ratings.length;i++) {
            if(ratings[i]>ratings[i-1]) {
                count[i] = count[i-1]+1;
            }
        }
         
        for(int i=ratings.length-1;i>0;i--) {
            sum+=count[i];
            if(ratings[i]<ratings[i-1] && count[i]>=count[i-1]) {
                count[i-1] = count[i]+1;
            }
        }
        sum+=count[0];
         
        return sum;
    }
}