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.

What difficulty level is this interview question?

This is a medium difficulty Coding & Algorithms question, commonly asked during Technical Screen rounds at Bytedance.

What role is this question designed for?

This question is commonly asked for Software Engineer candidates at Bytedance during technical interviews.

Solve these string, subset, and date problems | Bytedance Interview Question

Quick Overview

This multi-part question evaluates string and array manipulation, in-place algorithm implementation, combinatorial subset generation with and without duplicate handling, and calendar date arithmetic, testing competencies in algorithm design, complexity analysis, and edge-case handling within the Coding & Algorithms domain and requiring both conceptual understanding and practical implementation skills. Such problems are commonly asked in technical interviews to gauge a candidate's ability to implement efficient algorithms, reason about permutations and deduplication, manage memory constraints for in-place operations, and correctly handle date calculations and input edge cases.

You are asked to solve multiple coding tasks.

Reverse word order in a string

Input: a string s containing words separated by spaces (may contain leading/trailing spaces and multiple spaces between words).
Output: a string where the order of words is reversed , with exactly one space between words, and no leading/trailing spaces .
Example: " the sky is blue " -> "blue is sky the"

Follow-up: If the input is a mutable character array (e.g., char[]), modify it in place (O(1) extra space) to achieve the same result.

All subsets (no duplicates in input)

Input: an integer array nums where all elements are distinct.
Output: return all possible subsets (the power set). Order does not matter.

All unique subsets (duplicates allowed in input)

Input: an integer array nums that may contain duplicates.
Output: return all unique subsets (no duplicate subsets in the output).

Days between two dates

Input: two dates date1 and date2 in the format YYYY-MM-DD .
Output: return the absolute number of days between the two dates.
Assume valid Gregorian calendar dates.

Quick Overview

You are asked to solve multiple coding tasks.

Reverse word order in a string

Input: a string s containing words separated by spaces (may contain leading/trailing spaces and multiple spaces between words).
Output: a string where the order of words is reversed , with exactly one space between words, and no leading/trailing spaces .
Example: " the sky is blue " -> "blue is sky the"

Follow-up: If the input is a mutable character array (e.g., char[]), modify it in place (O(1) extra space) to achieve the same result.

All subsets (no duplicates in input)

Input: an integer array nums where all elements are distinct.
Output: return all possible subsets (the power set). Order does not matter.

All unique subsets (duplicates allowed in input)

Input: an integer array nums that may contain duplicates.
Output: return all unique subsets (no duplicate subsets in the output).

Days between two dates

Input: two dates date1 and date2 in the format YYYY-MM-DD .
Output: return the absolute number of days between the two dates.
Assume valid Gregorian calendar dates.

Solve these string, subset, and date problems

Quick Overview

Submit Your Answer

Solve these string, subset, and date problems

Quick Overview

Submit Your Answer