Example: Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7. return its minimum depth = 2. A binary tree of depth “d” is an almost complete binary tree if A Each leaf in the tree is either at level “d” or at level “d–1” B For any node “n” in the tree with a right descendent at level “d” all the left descendents of “n” that are leaves, are also at level “d” Complete Binary Tree: A Binary Tree is a complete Binary Tree if all the levels are completely filled except possibly the last level and the last level has all keys as left as possible The following are examples of Complete Binary Trees . ... if the depth of the binary is n the no. Proof that an almost complete binary tree with n nodes has at least $\frac{n}{2}$ leaf nodes 1 Can the structure of a “Complete Binary Tree”, be uniquely identified if only its pre-order or post-order or in-order traversals are given? To find the depth of the binary tree we will recursively calculate the depth of the left and right child of a node. Nearly Complete Binary Trees and Heaps DEFINITIONS: i) The depth of a node p in a binary tree is the length (number of edges) of the path from the root to p. ii) The height (or depth) of a binary tree is the maxi-mum depth of any node, or −1 if the tree is empty. ALMOST COMPLETE BINARY TREE-When the exception in the definition of complete binary tree holds then it is called almost complete binary tree or nearly complete binary tree . Clearly, for every function f: {0, 1} m → {0, 1} there is a decision tree of depth m (created simply by writing a complete binary tree of depth m, where all nodes in level i of the tree are labeled x i in this case each of the 2 m leaves corresponds to a single assignment; the … The depth of binary tree is the depth of the deepest node (leaf node). It is just a type of complete binary tree itself , but a separate definition is necessary to make it more unambiguous. Almost complete binary trees are not necessarily strictly binary (although they can be), and are not complete. Heaps A binary heap is defined as follows: It it an "almost" complete binary tree. Also, in the last level, nodes should be attached starting from the left-most position. As shown in figure 2, a complete binary tree is a binary tree in which every level of the tree is completely filled except the last level. What is Complete Binary Tree? That question is unfortunately more interesting than it should be since there are conflicting naming traditions out there, even in the standard text books. Note: A leaf is a node with no children. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. If the tree has a maximum level of d, then the subtree containing all the nodes from the root to level d-1 is a complete tree. Since the number of nodes in a complete binary tree of height h is 2 h+1-1, a complete binary tree with n nodes must be of height h = log 2 (n+1) - 1 = O(ln n). A complete binary tree of height h satisfies the following conditions: 18 / \ 15 30 / \ … The depth of complete binary tree of n nodes will be Dn=log 2 (n+1). Given a binary tree, find its minimum depth. There is a difference between complete binary tree and full binary tree. A complete binary tree is a binary tree in which every level, except possibly the last, is completely filled, and all nodes in the last level are filled in left to right order. Any binary tree can have at most 2d nodes at depth d. A complete binary tree is a binary tree where all the levels have maximum number of nodes except possibly the last level. In a complete binary tree of height 'h' there can be [2^h 2^(h+1) - 1] nodes. Here Dn is the height or depth of the tree and n is the number of nodes.