Solve array modulo and parentheses tasks

Q: Solve array modulo and parentheses tasks

This question evaluates proficiency in modular arithmetic and subarray-sum reasoning for remainder counting, together with string manipulation and parentheses-balancing competencies, testing algorithmic problem-solving, correctness justification, and implementation skills in the Coding & Algorithms domain.

Q: How do I approach Coding & Algorithms interview questions?

Coding & Algorithms questions require understanding of core concepts and practice. PracHub provides solutions with explanations to help you master coding & algorithms interviews.

Question

Implement two tasks:

Count subarrays by modulo remainder

Input: integer array nums (length n), integers K (1 ≤ K ≤ 10^

and R (0 ≤ R < K).

Output: the number of subarrays [i..j] such that (sum(nums[i..j]) mod K) == R.
Requirements: O(n) time and O(K) space; describe the approach, justify correctness, and analyze complexity. Provide an implementation of countSubarraysByRemainder(nums, K, R).

Remove the minimum parentheses to balance a string

Input: string s containing lowercase letters and parentheses '()'.
Output: any string formed by deleting the minimum number of parentheses so that the result is a valid, balanced parentheses string (characters’ relative order must be preserved).
Requirements: O(n) time and O(

extra space beyond the output; describe the algorithm and provide an implementation.

Solve array modulo and parentheses tasks

Overview

Comments (0)