I was given three problems to complete on HackerRank and 75 minutes to finish them.

I can only recall two of the questions.

Both of them had to do with arrays: one involved a 1-D array and the other a 2-D array.

Write a function that takes an array of integers and returns the maximum sum of a contiguous subarray.

Given an n x n matrix where cell values represent the resistance of a fluid, find the minimum path through the matrix, going from anywhere on the left column to the right column. Possible moves are top-right, right, and bottom-right.

Constraints:

• n < 100
• -100 < matrix[i][j] < 100