Leetcode: Search for a Range

Given a sorted array of integers, find the starting and ending position of a given target value.

Your algorithm's runtime complexity must be in the order of O(log n).

If the target is not found in the array, return [-1, -1].

For example,
Given [5, 7, 7, 8, 8, 10] and target value 8,
return [3, 4].

Solution

public class Solution {
    public int[] searchRange(int[] A, int target) {
        int[] solution = {-1,-1};
        int start = 0;
        int end = A.length-1;
        while(start<end)
        {
            int midpoint = (start+end)/2;
            if (A[midpoint]==target)
                end = midpoint;
            else if (A[midpoint]<target)
                start = midpoint+1;
            else
                end = midpoint-1;
        }
        if (A[start] !=target)
            return solution;
        else
            solution[0]=start;
        end = A.length -1;
        while(start<end)
        {
            int midpoint = (start+end+1)/2;
            if (A[midpoint]==target)
                start = midpoint;
            else
                end = midpoint-1;
        }
        solution[1]= start;
        return solution;
    }
}