# Binary Tree

 Question 1
Consider the C function foo and the binary tree shown.

typedef struct node {
int val;
struct node *left, *right;
} node;

int foo(node *p) {
int retval;
if (p == NULL)
return 0;
else {
retval = p->val + foo(p->left) + foo(p->right);
printf("%d ", retval);
return retval;
}
}

When foo is called with a pointer to the root node of the given binary tree, what will it print?
 A 3 8 5 13 11 10 B 3 5 8 10 11 13 C 3 8 16 13 24 50 D 3 16 8 50 24 13
GATE CSE 2023   Data Structure
Question 1 Explanation:
 Question 2
Consider a complete binary tree with 7 nodes. Let A denote the set of first 3 elements obtained by performing Breadth-First Search (BFS) starting from the root. Let B denote the set of first 3 elements obtained by performing Depth-First Search (DFS) starting from the root.

The value of |A-B| is _____________
 A 3 B 4 C 1 D 2
GATE CSE 2021 SET-2   Data Structure
Question 2 Explanation:

 Question 3
The post-order traversal of binary tree is ACEDBHIGF. The pre-order traversal is
 A A B C D E F G H I B F B A D C E G I H C F A B C D E G H I D A B D C E F G I H
ISRO CSE 2020   Data Structure
Question 3 Explanation:
 Question 4
Let T be a full binary tree with 8 leaves. (A full binary tree has every level full.) Suppose two leaves a and b of T are chosen uniformly and independently at random. The expected value of the distance between a and b in T (i.e., the number of edges in the unique path between a and b) is (rounded off to 2 decimal places) ___________ .
 A 2.5 B 4.25 C 6.5 D 3.75
GATE CSE 2019   Data Structure
Question 4 Explanation:
 Question 5

Which traversals of Tree-1 and Tree-2, respectively, will produce the same sequence?
 A Preorder, postorder B Postorder, inorder C Postorder, preorder D None of these
ISRO CSE 2018   Data Structure
Question 5 Explanation:

There are 5 questions to complete.

### 5 thoughts on “Binary Tree”

1. In Question no 8.
Sir please correct option no C)
to
-+1*76^2-5*43

• Thank You Abhishek Chavle,