I don't know why, but git needs me to commit

matrix.c

@@ -28,17 +28,47 @@ void clearMatrix(Matrix *matrix)
 
 void setMatrixAt(MatrixType value, Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    
+    if (rowIdx >= matrix.rows || colIdx >= matrix.cols){
+        printf("Index out of bounds\n"); //Error Message because Index Input exceeds Matrix
+}
+    else{
+        matrix.buffer[rowIdx * matrix.cols + colIdx] = value; //Writes Value of value variable in the selected place in Matrix
+}
 }
 
 MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int colIdx)
 {
-    
+    if (rowIdx >= matrix.rows || colIdx >= matrix.cols){
+       printf("Index out of bounds\n");
+       return 0;
+    }
+    else{
+
+       MatrixType value = matrix.buffer[rowIdx * matrix.cols + colIdx]; //Stores value of selected place of Matrix in value variable
+        return value;
 }
+  }
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
 {
-    
+    Matrix MatrixErgebnis = createMatrix(matrix1.rows, matrix1.cols); //Creating Result Matrix
+    if(matrix1.cols != matrix2.cols || matrix1.rows != matrix2.rows){
+        printf("Matrix dimensions do not match\n"); //Error Message if dimensions of Input Matrixes are not identical
+        MatrixErgebnis = clearMatrix(MatrixErgebnis);
+        return MatrixErgebnis;
+    }
+    else{
+
+        for (unsigned int i = 0; i < matrix1.rows; i++){
+            for (unsigned int j = 0; j < matrix1.cols; j++){
+                //Adding Matrix Elements of same row and col index together and store in new Matrix
+                MatrixErgebnis.buffer[i * matrix1.cols + j] = matrix1.buffer[i * matrix1.cols + j] + matrix2.buffer[i * matrix1.cols + j];
+
+                }
+        }
+
+  }
+return MatrixErgebnis;
 }
 
 Matrix multiply(const Matrix matrix1, const Matrix matrix2)