NPCI recently visited my campus for various roles, including Blockchain, Analyst, and Development positions. There was a shortlisting process before the first round.

Round 1: Online Assessment

This round had a duration of 1.5 hours and was divided into several sections:

• Aptitude: Approximately 12 questions with a moderate difficulty level.
• Verbal Reasoning: Similar to aptitude, with a moderate level of difficulty.
• Machine Learning: 20 questions on ML, some of which were quite challenging.
• Coding Round: Two questions, both at a medium difficulty level.

The coding questions were:

1. Given an array arr of N numbers. Each time the minimum number in the array is selected, its adjacent elements and the number itself are deleted. This process is repeated until there are no numbers left in the array. I was asked to find and print the total of the minimum numbers being deleted from the array.
2. Given a matrix mat of size m x n. Each cell of a matrix contains strength. A robot needs a positive strength to travel from the top left corner of the matrix to the bottom right corner. At any point of the journey, its strength cannot drop to 0 or less. The cells can contain either 0, positive or negative strength. Positive strength increases the robot’s strength by cell value, negative strength decreases its strength by cell value, and no change in strength if the cell value is 0. I was required to calculate the minimum initial strength required by the robot to travel from the source (i.e. the top left corner) to reach the destination (i.e. the bottom right corner) and print the same. Note: A robot can only move one cell at a time, either down or right. (e.g., to cell (i+1,j) or cell (i,j+1)) and it cannot move outside the matrix. mat[0][0] and mat[m-1][n-1] were stated to be 0.

Round 2: Final Round (Technical + HR)

This round lasted about 20-25 minutes. The discussion points included:

• Detailed discussion about projects mentioned in my resume.
• Machine Learning Questions: I had to explain concepts like K-means, the elbow method, CNN vs LSTM, and CNN vs ANN.
• SQL Questions: I was asked to explain joins, Outer Join, and provide their syntax.
• DSA Question: I was given the problem "Product Array Puzzle" to solve, with the specific constraint that the divide operation cannot be used.
• Other topics: What are indexes in Databases, and the difference between DELETE and Truncate.
• Finally, I was asked about other Machine Learning algorithms I knew and had to explain one of them.