Please help me with this Breadth- First-Search function.

Difference of Pairs on a BST: Write a method/function that outputs two pointers pointing to two nodes, x and y. in a given BST. where the key values of x and y differ by a given integer k. Recall that we had given the following algorithm in lecture that on an sorted input array A and given value k returns two indices i and j. where A[i] - A[j] = k. or report error if such i and j do not exist: i leftarrow 1; j leftarrow 2 n leftarrow length [A]//assuming indices of A start with 1 while (j lessthanorequalto n and i lessthanorequalto n) d leftarrow A[i] - A[j] if (d==k) return (i, j) if (d