码迷,mamicode.com
首页 > 其他好文 > 详细

【LeetCode】Candy

时间:2014-11-22 21:26:58      阅读:221      评论:0      收藏:0      [点我收藏+]

标签:style   blog   http   io   ar   color   sp   for   strong   

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

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 0;
        
        vector<int>::size_type size = ratings.size();
        vector<int> candies(size, 1);
        //from left to right
        for(vector<int>::size_type st = 1; st < size; st ++)
        {
            if(ratings[st] > ratings[st-1])
                candies[st] = candies[st-1]+1;
            //else if(ratings[st] < ratings[st-1])
            //    candies[st] = 1;
            //else
            //    candies[st] = 1;
        }
        //from right to left
        int Sum = candies[size-1];
        for(int st = size-2; st >= 0; st --)
        {//attention!!! if st is unsigned int, it will out of range
            if(ratings[st] > ratings[st+1])
                candies[st] = max(candies[st], candies[st+1]+1);
            //else if(ratings[st] < ratings[st+1])
             //   candies[st] = max(candies[st], 1);
            //else
            //    candies[st] = max(candies[st], 1);
            Sum += candies[st];
        }

        return Sum;
    }
};

bubuko.com,布布扣

 

【LeetCode】Candy

标签:style   blog   http   io   ar   color   sp   for   strong   

原文地址:http://www.cnblogs.com/ganganloveu/p/4115571.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!