This code is written as a part of a coding challenge. The challenge requires the user to write code that can convert a simple matrix into Compressed Sparse Row format and multiply it with any array and outputs the result in to a caller provided buffer. The code does not allocate any memory and uses pre allocated memory from the caller.

1. The code uses two main sections.
2. The first section converts the Matrix into the Compressed Sparse Row format. And the Second Section multiplies the CSR data with the vector.
3. Test harness is included in the file with the code as well.
4. The code satisfies all the requirements outlined by the challenge.