题解 | #数字在升序数组中出现的次数#

public class Solution {
    public int GetNumberOfK(int [] array, int k) {
        return binSearch(array, k + 0.5) - binSearch(array, k - 0.5);
    }

    private int binSearch(int[] array, double v) {

        int right = array.length - 1;
        int left  = 0;

        while (left <= right) {
            int mid = (left + right) / 2;
            if (array[mid] < v) {
                left = mid + 1;
            } else {
                right = mid - 1;
            }
        }
        return left;
    }
}