Chetan Sales Interview Questions and Answers

The problem involves finding the number of distinct ways to climb to the Nth stair by taking one or two steps at a time.

• Use dynamic programming to solve this problem efficiently.

• The number of ways to reach the Nth stair is the sum of the number of ways to reach the (N-1)th stair and the (N-2)th stair.

• Handle large inputs by taking modulo 10^9+7 to avoid overflow.

• Example: For N=3, there are 3 ways to climb to the third stair: (0, 1, 2, 3), (0, 2, 3), and (0, 1, 3).

Count the number of trailing zeros in the factorial of a given number.

• To find the number of trailing zeros in N!, count the number of factors of 5 in the prime factorization of N.

• Each factor of 5 contributes to a trailing zero in the factorial.

• For example, for N=10, there are 2 factors of 5 in the prime factorization (5 and 10), so there are 2 trailing zeros.

Quick sort has O(n log n) time complexity on average, O(n^2) worst case. Merge sort has O(n log n) time complexity always.

• Quick sort has an average time complexity of O(n log n) due to its divide-and-conquer approach.

• Worst case for quick sort occurs when the pivot element is either the smallest or largest element in the array, leading to O(n^2) time complexity.

• Merge sort always has a time complexity of O(n log n) due to its consistent splitting and merging of subarrays.

Removing a node from a linked list without head or tail pointer

• Use the node to be removed's next node to copy its data and then delete the next node

• Update the current node's next pointer to skip the next node

My favorite programming language is Python because of its simplicity, readability, and versatility.

• Python is known for its clean and readable syntax, making it easy to learn and understand.

• Python has a large standard library and many third-party libraries, allowing for rapid development of a wide range of applications.

• Python is versatile and can be used for web development, data analysis, machine learning, automation, and more.