【LeetCode】135. Candy

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?

左右各遍历一次，依据前一个位置的candy数计算当前位置需要的最小candy数（最少为1）

由于两次遍历的结果都要满足，因此对同一位置取max即可。

class Solution {
public:
    int candy(vector<int>& ratings) {
        if(ratings.empty())
            return ;
        int n = ratings.size();
        vector<int> left(n, );
        for(int i = ; i < n; i ++)
        {
            if(ratings[i] > ratings[i-])
                left[i] = left[i-] + ;
        }
        vector<int> right(n, );
        int sum = max(left[n-], right[n-]);
        for(int i = n-; i >= ; i --)
        {
            if(ratings[i] > ratings[i+])
                right[i] = right[i+] + ;
            sum += max(left[i], right[i]);
        }
        return sum;
    }
};