Backend developer intern

A thief is robbing a store and can carry a maximum weight of ‘W’ into his knapsack. There are 'N' items available in the store and the weight and value of each item is known to the thief. Considering the constraints of the maximum weight that a knapsack can carry, you have to find the maximum profit that a thief can generate by stealing items.

Note: The thief is not allowed to break the items.

For example, N = 4, W = 10 and the weights and values of items are weights = [6, 1, 5, 3] and values = [3, 6, 1, 4]. Then the best way to fill the knapsack is to choose items with weight 6, 1 and 3. The total value of knapsack = 3 + 6 + 4 = 13.

You are given a matrix having ‘N’ rows and ‘M’ columns. Each cell of the matrix is either ‘X’ or ‘O’. You need to flip all those regions of ‘O’ which are surrounded by ‘X’ i.e. you need to change all ‘O’s which are present in the region to ‘X’.

Note

1. Surrounded regions shouldn’t be on the border, which means that any 'O' on the border of the matrix is not flipped to 'X'. 
2. Any ‘O’ or group of connected ‘O’ are said to be surrounded by ‘X’ when all cells touching the boundary of the group of ‘O’ must contain ‘X’.

For example

He discussed one of my projects (in progress) in detail. We discussed its System Design, and Schema details. 

Then he gave me some SQL queries to write based on those schemas. We also modified those schemas after discussions and I wrote another SQL query based on the updated schemas.

Interviewer asked basic details about APIs, GraphQL, and Kafka.