Caterpillar Inc HR Analyst Interview Questions and Answers

A stack is a Last In First Out (LIFO) data structure, while a queue is a First In First Out (FIFO) data structure.

• Stack: LIFO - Last In First Out. Example: browser history where the last page visited is the first to be accessed.

• Queue: FIFO - First In First Out. Example: a line at a grocery store where the first person in line is the first to be served.

Function to find two numbers in array that add up to target. Optimize solution.

• Use a hash map to store each number and its index as you iterate through the array.

• For each number, check if the difference between the target and the number exists in the hash map.

• Return the indices of the two numbers that add up to the target.