Spiral Matrix

Problem Statement

Given an m x n matrix, return all elements of the matrix in spiral order.

Examples

Example 1:

Input:
matrix = [[1,2,3],[4,5,6],[7,8,9]]
Output:
[1,2,3,6,9,8,7,4,5]

Example 2:

Input:
matrix = [[1,2,3,4],[5,6,7,8],[9,10,11,12]]
Output:
[1,2,3,4,8,12,11,10,9,5,6,7]

Constraints

• m == matrix.length
• n == matrix[i].length
• 1 <= m, n <= 10
• -100 <= matrix[i][j] <= 100

Code Template

class Solution:
    def spiralOrder(self, matrix: List[List[int]]) -> List[int]:
        # Your code here
        pass

Solutions

• Solution 1: This approach uses four pointers to track the boundaries of the matrix and iteratively collects elements in a spiral order. The time complexity is O(m*n) and space complexity is O(1) for the output list.

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