public class Solution {
    public int GetNumberOfK(int [] array , int k) {
        if(array == null || array.length == 0) {
            return 0;
        }
       int le = 0, ri = array.length - 1, mid = 0;
        while(le < ri) {
            mid = (le + ri) / 2;
            if(array[mid] == k) {
                break;
            } else if(array[mid] > k) {
                ri = mid - 1;
            } else {
                le = mid + 1;
            }
        }
        if(array[mid] != k) {
            return 0;
        }
        le = mid;
        while(le > -1 && array[le] == k) le--;
        ri = mid;
        while(ri < array.length && array[ri] == k) ri++;
        return ri - 1 - le;
    }
}