Spiral Matrix IV

Spiral Matrix IV is a Medium Data Structures and Algorithms interview problem you can solve, run and submit on Thita.ai. It belongs to the Array/Matrix Manipulation Patterns pattern, in the Spiral Traversal subpattern.

Problem statement

You are given two integers m and n, which represent the dimensions of a matrix.

You are also given the head of a linked list of integers.

Generate an m x n matrix that contains the integers in the linked list presented in spiral order (clockwise), starting from the top-left of the matrix. If there are remaining empty spaces, fill them with -1.

Return the generated matrix.

Example 1:

Input: m = 3, n = 5, head = [3,0,2,6,8,1,7,9,4,2,5,5,0] Output: [[3,0,2,6,8],[5,0,-1,-1,1],[5,2,4,9,7]] Explanation: The diagram above shows how the values are printed in the matrix. Note that the remaining spaces in the matrix are filled with -1.

Example 2:

Input: m = 1, n = 4, head = [0,1,2] Output: [[0,1,2,-1]] Explanation: The diagram above shows how the values are printed from left to right in the matrix. The last space in the matrix is set to -1.

Constraints:

- 1 <= m, n <= 105

- 1 <= m n <= 105

- The number of nodes in the list is in the range [1, m n].

- 0 <= Node.val <= 1000

Topics and companies

Topics: Array, Linked List, Matrix, Simulation.

How to practise Spiral Matrix IV on Thita.ai

Starter code is provided in C, C#, C++, Go, Java, JavaScript and Python. Your solution runs against 5 test cases for this problem, with the AI coach available for a hint when you are stuck rather than a finished answer. The reference solution runs in O(m * n). Each cell in the matrix is visited at most once, and each value from the input list is placed in the matrix in spiral order. time and O(m * n). The output matrix of size m x n is created and returned. No extra space proportional to input size is used beyond the result. space.

Open Spiral Matrix IV in the code editor, or read the Spiral Matrix IV editorial for a worked solution with its approach and complexity analysis.

Where Spiral Matrix IV sits in the DSA pattern sheet

Problems related to Spiral Matrix IV

Other problems that use the same Spiral Traversal and Array/Matrix Manipulation Patterns techniques:

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