From 645d4718606fa4d718b8108f4b0fa7ef95731d39 Mon Sep 17 00:00:00 2001
From: Simon Wiesend <117300309+smnws@users.noreply.github.com>
Date: Tue, 11 Nov 2025 19:05:03 +0100
Subject: [PATCH] first implementation of new broadcasting addition requirement

---
 matrix.c | 41 ++++++++++++++++++++++++++++++++++++-----
 1 file changed, 36 insertions(+), 5 deletions(-)

diff --git a/matrix.c b/matrix.c
index 917a8b2..4d42efd 100644
--- a/matrix.c
+++ b/matrix.c
@@ -58,13 +58,44 @@ MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int co
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
 {
-    Matrix resMat = createMatrix(matrix1.rows, matrix1.cols);
+    Matrix resMat = (matrix1.cols > matrix2.cols) ? createMatrix(matrix1.rows, matrix1.cols) : createMatrix(matrix2.rows, matrix2.cols);
 
-    // clear matrix and return if the dimensions of the input matrices differ from each other
-    if (matrix1.rows != matrix2.rows || matrix1.cols != matrix2.cols)
+    if (matrix1.cols != matrix2.cols)
     {
-        clearMatrix(&resMat);
-        return resMat;
+        if (matrix1.rows != matrix2.rows)
+        {
+            clearMatrix(&resMat);
+            return resMat;
+        }
+        else if (matrix1.cols == 1)
+        {
+            // broadcast vector
+            for (size_t m = 0; m < matrix2.rows; m++)
+            {
+                for (size_t n = 0; n < matrix2.cols; n++)
+                {
+                    setMatrixAt(getMatrixAt(matrix2, m, n) + getMatrixAt(matrix1, m, 0), resMat, m, n);
+                }
+            }
+            return resMat;
+        }
+        else if (matrix2.cols == 1)
+        {
+            // broadcast vector
+            for (size_t m = 0; m < matrix1.rows; m++)
+            {
+                for (size_t n = 0; n < matrix1.cols; n++)
+                {
+                    setMatrixAt(getMatrixAt(matrix1, m, n) + getMatrixAt(matrix2, m, 0), resMat, m, n);
+                }
+            }
+            return resMat;
+        }
+        else
+        {
+            clearMatrix(&resMat);
+            return resMat;
+        }
     }
 
     for (size_t m = 0; m < matrix1.rows; m++)