diff --git a/matrix.c b/matrix.c
index 85f8497..0655d72 100644
--- a/matrix.c
+++ b/matrix.c
@@ -6,14 +6,12 @@
 
 Matrix createMatrix(unsigned int rows, unsigned int cols)
 {
-    Matrix m;
+    Matrix m = {0, 0, NULL};
 
-    m.buffer = NULL;
-    m.rows = rows;
-    m.cols = cols;
-
-    if (rows > 0 || cols > 0)
+    if (rows > 0 && cols > 0)
     {
+        m.rows = rows;
+        m.cols = cols;
         m.buffer = malloc(rows * cols * sizeof(int));
     }
 
@@ -46,7 +44,12 @@ MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int co
 {
     MatrixType value = 0;
 
-    return value = matrix.buffer[rowIdx * matrix.cols + colIdx]; // hole Wert value am Punkt (row col)
+    if (rowIdx < matrix.rows && colIdx < matrix.cols)
+    {
+        value = matrix.buffer[rowIdx * matrix.cols + colIdx]; // hole Wert value am Punkt (row col)
+    }
+
+    return value;
 }
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
@@ -85,7 +88,7 @@ Matrix multiply(const Matrix matrix1, const Matrix matrix2)
 {
     Matrix result = {0};
 
-    if (matrix1.cols != matrix2.rows)
+    if (matrix1.rows != matrix2.rows || matrix1.cols != matrix2.cols)
     {
         return result;
     }
diff --git a/matrix.h b/matrix.h
index 595ac23..fb042ea 100644
--- a/matrix.h
+++ b/matrix.h
@@ -11,7 +11,6 @@ typedef struct
 {
     unsigned int rows;   // Anzahl der Zeilen
     unsigned int cols;   // Anzahl der Spalten
-    //void *buffer;
     MatrixType *buffer;    // Zeiger auf die Matrixdaten 
 } Matrix;