[LeetCode] Assign Cookies

Problem: 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 g[i], which is the minimum size of a cookie that the child will be content with; and each cookie j has a size s[j]. If s[j] >= g[i], 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.

Example:

Input: g = [1,2,3], s = [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

Input: g = [1,2], s = [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: If we sort both the arrays the problem becomes straight forward of just comparing the greed factor and cookie size.

Implementation in C#:

    public int FindContentChildren(int[] g, int[] s) 

    {

        Array.Sort(g);

        Array.Sort(s);

        int gi = 0;

        int si = 0;

        while(gi < g.Length && si < s.Length)

        {

            if (s[si] >= g[gi])

            {

                ++gi;  

            }            

            ++si;

        }        

        return gi;

    }

Complexity: O(nlogn)