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Implement array rotations and CSV keyword search | Warner Bros Discovery Interview Question

Q: Implement array rotations and CSV keyword search

This question evaluates array manipulation and string parsing competencies, focusing on rotating arrays via modular index arithmetic and locating substring occurrences within a simple CSV while mapping each match to row, column, and character position.

Problem A — Rotate an array left/right by k

You are given an integer array nums of length n and an integer k.

Implement rotateLeft(nums, k) that returns the array after rotating it left by k positions.
Implement rotateRight(nums, k) that returns the array after rotating it right by k positions.

Notes / Constraints

k can be larger than n ; treat k as k % n .
Handle edge cases like n = 0 or n = 1 .
Clarify in your solution whether you modify in-place or return a new array.

Example

nums = [1,2,3,4,5] , k = 2
- left rotate → [3,4,5,1,2]
- right rotate → [4,5,1,2,3]

Problem B — Find keyword occurrences in a CSV text

You are given a CSV document as a single string csvText.

Rows are separated by newline characters \n .
Columns are separated by commas , .
Assume fields do not contain escaped commas or quoted strings (i.e., simple CSV).

Task

Given csvText and a keyword key, return all occurrences of key in the document.

For each occurrence, return:

row : the 0-based row number
col : the 0-based column number
pos : the 0-based character index within that cell where the match begins

Return results in row-major order.

Variant

Extend the function to accept multiple keywords keys[] and return occurrences for any of them (you may also include which keyword matched).

Example

csvText = "foo,bar\nxxfood,barfoo", key = "foo"

Row 0, Col 0, Pos 0 ("foo")
Row 1, Col 0, Pos 2 ("xxfood")
Row 1, Col 1, Pos 3 ("barfoo")

(Exact output format is up to you; it just needs to include row/col/pos.)

Problem A — Rotate an array left/right by k

You are given an integer array nums of length n and an integer k.

Implement rotateLeft(nums, k) that returns the array after rotating it left by k positions.
Implement rotateRight(nums, k) that returns the array after rotating it right by k positions.

Notes / Constraints

k can be larger than n ; treat k as k % n .
Handle edge cases like n = 0 or n = 1 .
Clarify in your solution whether you modify in-place or return a new array.

Example

nums = [1,2,3,4,5] , k = 2
- left rotate → [3,4,5,1,2]
- right rotate → [4,5,1,2,3]

Problem B — Find keyword occurrences in a CSV text

You are given a CSV document as a single string csvText.

Rows are separated by newline characters \n .
Columns are separated by commas , .
Assume fields do not contain escaped commas or quoted strings (i.e., simple CSV).

Task

Given csvText and a keyword key, return all occurrences of key in the document.

For each occurrence, return:

row : the 0-based row number
col : the 0-based column number
pos : the 0-based character index within that cell where the match begins

Return results in row-major order.

Variant

Extend the function to accept multiple keywords keys[] and return occurrences for any of them (you may also include which keyword matched).

Example

csvText = "foo,bar\nxxfood,barfoo", key = "foo"

Row 0, Col 0, Pos 0 ("foo")
Row 1, Col 0, Pos 2 ("xxfood")
Row 1, Col 1, Pos 3 ("barfoo")

(Exact output format is up to you; it just needs to include row/col/pos.)

Implement array rotations and CSV keyword search

Quick Overview

Problem A — Rotate an array left/right by k

Notes / Constraints

Example

Problem B — Find keyword occurrences in a CSV text

Task

Variant

Example

Submit Your Answer to Earn 20XP

Implement array rotations and CSV keyword search

Quick Overview

Problem A — Rotate an array left/right by k

Notes / Constraints

Example

Problem B — Find keyword occurrences in a CSV text

Task

Variant

Example

Submit Your Answer to Earn 20XP