455. Assign Cookies

你的名字 2022-04-23 08:58 167阅读 0赞

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.

已知一些孩子和一些糖果，每个孩子有需求因子g，每个糖果有大小s，当某些糖果的大小s>=某个孩子的需求因子g时，代表该糖果可以满足孩子；求使用这些糖果，最多能满足多少孩子？（注意：某个孩子最多只能有1个糖果满足）

解法：先对g, s排序，然后使用贪心法。 某个糖果如果**不能满足**某个孩子，则该糖果也**一定不能**满足需求因子**更大**的孩子。某个孩子可以用**更小**的糖果满足，则没必要**更大糖果**满足，因为可以**保留**更大的糖果满足需求因子更大的孩子（贪心）。

class Solution {
    public:
        int findContentChildren(vector<int>& g, vector<int>& s) {
        sort(g.begin(),g.end());
    	sort(s.begin(), s.end());
    	int child = 0, cookie = 0;
    	while (child < g.size() && cookie < s.size())
    	{
    		if (g[child] <= s[cookie])
    		{
    			child++;
    		}
    		cookie++;
    	}
    	return child;   
        }
    };