10+ Knack Global Interview Questions and Answers

Swap each even position bit of an integer with its adjacent odd bit to the right in binary representation.

• Iterate through the binary representation of the integer and swap adjacent bits at even positions with odd positions.

• Convert the modified binary representation back to an integer to get the final result.

• Handle edge cases like leading zeros in binary representation.

Return the level order traversal of a Binary Tree of integers.

• Perform a level order traversal using a queue data structure

• Start by pushing the root node into the queue

• Pop each node from the queue, print its value, and push its children into the queue

Components of an IP packet header

• Version

• Header Length

• Type of Service

• Total Length

• Identification

• Flags

• Fragment Offset

• Time to Live

• Protocol

• Header Checksum

• Source IP Address

• Destination IP Address

• Options

The TCP segment header consists of various components that help in the transmission of data over a network.

• Source Port

• Destination Port

• Sequence Number

• Acknowledgment Number

• Data Offset

• Reserved

• Flags

• Window Size

• Checksum

• Urgent Pointer

Swapping two particular bits of an integer program.

• Use bitwise operators to get the values of the two bits to be swapped

• Use XOR operator to swap the bits

• Shift the bits back to their original positions

• Example: Swapping 2nd and 5th bits of 8 (1000) gives 32 (100000)

• Example code: num ^= (1 << bit1) | (1 << bit2);

TCP is connection-oriented, reliable, and slower, while UDP is connectionless, unreliable, and faster.

• TCP is connection-oriented, meaning it establishes a connection before sending data, while UDP is connectionless and does not establish a connection.

• TCP is reliable as it ensures all data packets are received in order and retransmits any lost packets, while UDP does not guarantee delivery or order of packets.

• TCP is slower than UDP due to the overhead of error-checking, flow c...read more

IP packet header fields and their usage

• Version: indicates the IP version being used (IPv4 or IPv6)

• Header Length: specifies the length of the IP header

• Type of Service: used to prioritize packets

• Total Length: specifies the total length of the IP packet

• Identification: used to identify fragments of a larger packet

• Flags: used to control fragmentation

• Fragment Offset: used to reassemble fragmented packets

• Time to Live: specifies the maximum number of hops a packet can take

• Protocol: s...read more

TCP packet header fields and their usage

• TCP packet header consists of 20 bytes

• Fields include source and destination ports, sequence and acknowledgement numbers, flags, window size, and checksum

• Source and destination ports identify the endpoints of the connection

• Sequence and acknowledgement numbers are used for reliable data transfer

• Flags indicate the purpose of the packet, such as SYN, ACK, FIN, RST

• Window size is used for flow control

• Checksum is used for error detection

Security is important in a system to protect against unauthorized access, data breaches, and cyber attacks.

• Prevents unauthorized access to sensitive data

• Protects against data breaches and cyber attacks

• Ensures confidentiality, integrity, and availability of data

• Compliance with regulations and standards

• Maintains trust and confidence of customers and stakeholders

Implement a telephone directory program using an array of strings.

• Create an array of strings to store the directory

• Implement functions to add, delete, and search for entries

• Consider using a hash table for faster search times

• Include error handling for invalid input

Printing a tree in level order

• Use a queue to store nodes in level order

• Enqueue root node and print its value

• Dequeue the node and enqueue its children

• Repeat until queue is empty

A program to implement a dictionary using an array of strings.

• Use an array of strings to store the words and their definitions.

• Implement functions to add, delete, and search for words.

• Consider using a hash table for faster search times.