You have been given a recursive function to sum the values of all keys in a BST int findsum(TreeNode " root, int depth) if (root !- NULL) int leftSum - findSum(root->left, depth1); int rightSum - findSum(root->right, depth1) cout key; if (depth 1-) cout keys else return ; Consider following binary search tree: 15 12 17 The following code is called: findSum(root, e); Root is a pointer to the TreeNode whose key is 15. What is the output from cout? Note that there is a single space between values that are printed to the terminal. Note, there are no intended errors in the code