CODE 99. Search for a Range

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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].

public int[] searchRange(int[] A, int target) {
	// IMPORTANT: Please reset any member data you declared, as
	// the same Solution instance will be reused for each test case.
	int start = 0;
	int end = A.length - 1;
	while (start < end) {
		int mid = (start + end) / 2;
		if (A[mid] < target) {
			start = mid + 1;
		} else if (A[mid] >= target) {
			end = mid;
		}
	}
	if (A[start] != target
			&& ((start + 1 < A.length && A[start + 1] != target) || (start + 1 >= A.length))) {
		return new int[] { -1, -1 };
	}
	if (A[start] != target && start + 1 < A.length
			&& A[start + 1] == target) {
		start++;
	}
	for (end = start + 1; end < A.length; end++) {
		if (A[end] != target) {
			break;
		}
	}
	return new int[] { start, end - 1 };
}