Consider you have an infinitely long binary tree having the pattern as below
1
/ \
2 3
/ \ / \
4 5 6 7
. . . . . . . .
Given two nodes with values x and y, the task is to find the length of the shortest path between the two nodes.
Example 1:
Input:
X = 1
Y = 3
Output:
1
Explanation:
3 is the child of 1 so,
distance between them is 1.
Example 2:
Input:
X = 2
Y = 2
Output:
0
Explanation:
There is no node between 2 and 2.
Your Task:
You don't need to read input or print anything. Your task is to complete the function distance() which take integers X and Y as input parameters and returns the distance between X and Y in the infinitely long tree.

Expected Time Complexity: O(log (y - x))
Expected Auxiliary Space: O(1)
Constraints:
1<=X,Y<=10^{7}

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