candy

原文地址：https://www.jianshu.com/p/89d534c4ebf9

时间限制：1秒 空间限制：32768K

题目描述

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 neighbours.

What is the minimum candies you must give?

我的代码

class Solution {
public:
    int candy(vector<int> &ratings) {
        int n=ratings.size();
        if(n<1)
            return 0;
        if(n==1)
            return 1;
        vector<int> num(n,1);
        for(int i=1;i<n;i++)
            if(ratings[i]>ratings[i-1])
                num[i]=num[i-1]+1;//从左到右保证题目要求
        for(int i=n-2;i>=0;i--)
            if((ratings[i]>ratings[i+1])&&(num[i]<=num[i+1]))
                num[i]=num[i+1]+1;//从右到左保证题目要求
        int res=0;
        for(int i=0;i<n;i++)
            res+=num[i];
        return res;
    }
};

运行时间：22ms
占用内存：692k