Given n pieces of wood with length L[i] (integer array). Cut them into small pieces to guarantee you could have equal or more than k pieces with the same length. What is the longest length you can get from the n pieces of wood? Given L k, return the maximum length of the small pieces.

public class Solution {
    /** 
     *@param L: Given n pieces of wood with length L[i]
     *@param k: An integer
     *return: The maximum length of the small pieces.
     */
    public int woodCut(int[] L, int k) {
        // write your code here
        if (L == null || L.length == 0) return 0;
        
        Arrays.sort(L);
        int lo = 1, hi = L[L.length - 1], len = 0; // lo starts from 1, not L[0]
        while (lo <= hi) {
            int count = 0;
            int mid = lo + (hi - lo) / 2;//hi can be really large
            for (int n : L) {
                count += n / mid;
            }
            if (count >= k) {
                lo = mid + 1;
                len = mid;
            } else {
                hi = mid - 1;
            }
        }
        return len;
    }
}