[LeetCode]Candy

题目描述:(链接)

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?

解题思路：

开辟一个数组记录每个孩子的糖果数，前后两次扫描该数组，改变当前孩子的糖果数目。

class Solution {
public:
    int candy(vector<int>& ratings) {
        int n = ratings.size();
        vector<int> result(n);

        for (int i = 1; i < n; ++i) {
            if (ratings[i] > ratings[i - 1]) {
                result[i] = result[i - 1] + 1;
            }
        }

        for (int i = n - 2; i >= 0; --i) {
            if (ratings[i] > ratings[i + 1]) {
                result[i] = (result[i + 1] + 1 > result[i])? result[i + 1] + 1 : result[i];
            }
        }

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

        return sum + n;
    }
};