dfs that takes a TreeNode node, the array arr, and the current index i as arguments.node is null or i is equal to the length of arr, return false.node does not match arr[i], return false.i is at the last index of arr and node is a leaf, return true.dfs for the left and right children of node with the next index i + 1.true if either recursive call returns true, otherwise return false.dfs with the root of the tree, arr, and index 0.