How do you do search in an array where difference between adjacent elements is always 1

Problem statement: How do you do efficient search in an array where difference between adjacent elements is always 1

1. public class JumpSearch {
2. public static void main(String[] args) {
3. int a[] = { 9, 10, 11, 12, 11, 10, 9, 8, 7, 6, 7, 8, 9, 8, 7, 6, 5};
4. System.out.println(searchAlgo(a, 7)); // search element is 7
5. }
6. // 's' is the element to be searched in array a[0..n-1]
7. static int searchAlgo(int a[], int s) {
8. int n = a.length; // length of array
9. // scan the given array staring from leftmost element
10. int i = 0; // left first index
11. while (i < n) {
12. // check if element is found
13. if (a[i] == s) {
14. return i;
15. }
16. // else jump to diff. b/w current array element & search element
17. i = i + Math.abs(a[i] - s);
18. }
19. return -1; // element does not found
20. }
21. }

Output: 8

Time complexity: less than O(n)