455. Assign Cookies

#week16

Assume you are an awesome parent and want to give your children some cookies. But, you should give each child at most one cookie. Each child i has a greed factor gi, which is the minimum size of a cookie that the child will be content with; and each cookie j has a size sj. If sj >= gi, we can assign the cookie j to the child i, and the child i will be content. Your goal is to maximize the number of your content children and output the maximum number.

Note:
You may assume the greed factor is always positive. 
You cannot assign more than one cookie to one child.

Example 1:

Input: [1,2,3], [1,1]

Output: 1

Explanation: You have 3 children and 2 cookies. The greed factors of 3 children are 1, 2, 3. 
And even though you have 2 cookies, since their size is both 1, you could only make the child whose greed factor is 1 content.
You need to output 1.

Example 2:

Input: [1,2], [1,2,3]

Output: 2

Explanation: You have 2 children and 3 cookies. The greed factors of 2 children are 1, 2. 
You have 3 cookies and their sizes are big enough to gratify all of the children, 
You need to output 2.

分析

这一题看上去有点晕的样子

但是实际上也是一道简单的贪心

每个孩子有g[i]的曲奇

有s数组的曲奇

想让得到满足的孩子的数量尽可能多

因此将两个数组排个序

都从最大的开始分

分别比较

能够分到的就分

不能就往下一个孩子

然后计数一下就可以得到答案

题解

 1 class Solution {
 2 public:
 3     int findContentChildren(vector<int>& g, vector<int>& s) {
 4         sort(g.begin(),g.end());
 5         sort(s.begin(),s.end());
 6         int i=g.size()-1, j=s.size()-1,count = 0;
 7         while(i>=0 && j>=0)
 8         {
 9             if(g[i]>s[j]) i--;
10             else if(g[i--]<=s[j--]) count++;
11         }
12         return count;
13     }
14 };