Given the root of a binary tree and two integers p and q, return the distance between the nodes of value p and value q in the tree. The distance between two nodes is the number of edges on the path from one to the other. Example 1: Input: root = [3,5,1,6,2,0,8,null,null,7,4], p = 5, q = 0 Output: 3 Explanation: There are 3 edges between 5 and 0: 5-3-1-0. Example 2: Input: root = [3,5,1,6,2,0,8,null,null,7,4], p = 5, q = 7 Output: 2 Explanation: There are 2 edges between 5 and 7: 5-2-7. Example 3: Input: root = [3,5,1,6,2,0,8,null,null,7,4], p = 5, q = 5 Output: 0 Explanation: The distance between a node and itself is 0. Constraints: The number of nodes in the tree is in the range [1, 104]. 0 <= Node.val <= 109 All Node.val are unique. p and q are values in the tree.