Solved the question of spiral matrix traversal (leetcode)

[Ujjansh05]

Implemented a solution for the "Spiral Matrix" problem (LeetCode #54). The new file 54.C contains the function:

int* spiralOrder(int** matrix, int n, int m, int* returnSize)

which computes the elements of an n x m matrix in spiral order and returns a dynamically allocated array containing the traversal. The function updates *returnSize with the number of returned elements.

Key details:

Approach: Boundary-tracking traversal (top, bottom, left, right) that iteratively collects rows/columns while shrinking boundaries.

Time complexity: O(n * m) — each matrix element is visited exactly once.

Space complexity: O(n * m) for the returned array (output storage). No extra traversal buffers used.

Assumptions / Notes:
The function expects valid pointers for matrix and returnSize, and positive n and m.
The returned array is allocated with malloc; the caller is responsible for freeing it.
The implementation uses a traversal counter to avoid overrun when the matrix dimensions are uneven.

Suggested follow-ups (not required for this PR):

Add a small unit test / example harness (stdin-driven or fixed test cases) under leetcode/tests/ or repository test pattern.
Validate/handle the edge cases explicitly (e.g., n == 0 or m == 0, or NULL matrix) if the project style requires defensive checks.
Consider renaming the file to use a lowercase extension (54.c) if that matches the repository filename conventions.
References

Problem: LeetCode — Spiral Matrix: https://leetcode.com/problems/spiral-matrix/