455. Assign Cookies

Posted 2021-01-24 ruruozhenhao

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.

 

Approach #1: C++.

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

　　

Approach #2: Java.

class Solution {
    public int findContentChildren(int[] g, int[] s) {
        Arrays.sort(g);
        Arrays.sort(s);
        int i = 0, j = 0;
        while (j < s.length && i < s.length) {
            if (s[j] >= g[i])
                i++;
            j++;
        }
        return i;
    }
}

　　

Approach #3: Python.

class Solution(object):
    def findContentChildren(self, g, s):
        """
        :type g: List[int]
        :type s: List[int]
        :rtype: int
        """
        g.sort()
        s.sort()
        
        i, j = 0, 0
        
        while j < len(s) and i < len(g):
            if s[j] >= g[i]:
                i += 1
            j += 1
            
        return i