Apply commands to transform a matrix

Q: Apply commands to transform a matrix

This question evaluates array and matrix manipulation skills, specifically in-place row reversal, row swapping, and 90-degree rotation, and falls under the Coding & Algorithms domain with emphasis on practical implementation.

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Question

You are given an integer matrix A of size n × m and a list of string commands to apply in order. Implement the commands and return the final matrix.

Commands

Each command is one of:

"reverseRow r"
- r is a 0-based row index.
- Reverse the elements in row r in-place.
"swap r1 r2"
- r1 and r2 are 0-based row indices.
- Swap the two rows.
"rotate"
- Rotate the entire matrix 90 degrees clockwise.
- Note that after rotation, the matrix dimensions become m × n .

Input/Output

Input: A and commands .
Output: the matrix after applying all commands in order.

Assumptions / Constraints

0 ≤ r, r1, r2 < current_number_of_rows at the time the command is executed.
Matrix elements fit in 32-bit signed integers.
n, m ≥ 1 .

Example

If A = [[1,2,3],[4,5,6]] and commands = ["reverseRow 0", "rotate"], then:

After reverseRow 0 : [[3,2,1],[4,5,6]]
After rotate : [[4,3],[5,2],[6,1]] Return [[4,3],[5,2],[6,1]] .

Apply commands to transform a matrix

Overview

Commands

Input/Output

Assumptions / Constraints

Example

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