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?

思路： 先从左往右扫描一遍数组，使得右边等级比左边等级高的小朋友分得的糖果多1个，然后再从右往左扫描一遍数组使得左边等级比右边等级高的小朋友分得的糖果多。但是要注意的是，从右往左扫描数组的时候，如果当前小朋友的等级比他右边的小朋友的等级高，并且分得的糖果也比右边的小朋友的多，就不用修改了，如果修改的话，有可能把当前小朋友分得的糖果改少。

满足这个条件的才需要修改当前小朋友分得的糖果数：
ratings[i]>ratings[i+1] && nums[i]<=nums[i+1]

其中nums[i]用来表示小朋友分得的糖果数量

public class Solution {
    public int candy(int[] ratings) {
        int n=ratings.length;
        if(n<=0) return 0;
        if(n==1) return 1;
        int[] nums=new int[n];
        int sum=0;
        nums[0]=1;
        for(int i=1;i<n;i++)
        {
            if(ratings[i]>ratings[i-1])
              nums[i]=nums[i-1]+1;
            else nums[i]=1;
        }
        for(int i=n-2;i>=0;i--)
        {
            if(ratings[i]>ratings[i+1] && nums[i]<=nums[i+1])
                 nums[i]=nums[i+1]+1;

        }
        for(int i=0;i<n;i++)
          sum+=nums[i];

        return sum;
    }
}