diff --git a/imageInput.c b/imageInput.c
index 8bc6c23..977367e 100644
--- a/imageInput.c
+++ b/imageInput.c
@@ -21,30 +21,47 @@ int checkHeader(FILE* fileName)
 //// TODO Vervollständigen Sie die Funktion readImages unter Benutzung Ihrer Hilfsfunktionen
 GrayScaleImageSeries *readImages(const char *path)
 {
-  	 FILE* file = fopen(path,"rb");
+    FILE* file = fopen(path,"rb");
     unsigned int width=0,height=0;
-	GrayScaleImageSeries *imageSeries = malloc(sizeof(GrayScaleImageSeries));
+	GrayScaleImageSeries *imageSeries = (GrayScaleImageSeries*)malloc(sizeof(GrayScaleImageSeries));
+    if (imageSeries ==NULL) {
+        printf("Error allocating memory for GrayScaleImageSeries\n");
+        return NULL;
+    }
     imageSeries->count = 0;
     if(checkHeader(file) == 0) {
         fclose(file);
         return NULL;
     }
     fread(&imageSeries->count,sizeof(unsigned short),1,file);
-    imageSeries->images = malloc(imageSeries->count * sizeof(GrayScaleImage));
+    imageSeries->images = (GrayScaleImage*)malloc(imageSeries->count * sizeof(GrayScaleImage));
     fread(&width,sizeof(unsigned short),1,file);
     fread(&height,sizeof(unsigned short),1,file);
     imageSeries->labels = malloc(imageSeries->count * sizeof(unsigned char));
+    if(imageSeries->labels == NULL) {
+        free(imageSeries);
+        fclose(file);
+        return NULL;
+    }
+
     for(int i = 0; i < imageSeries->count; i++) {
        imageSeries->images[i].width = width;
         imageSeries->images[i].height = height;
        const unsigned int imageSize = height*width;
-        imageSeries->images[i].buffer = malloc(imageSize*sizeof(GrayScalePixelType));
+        imageSeries->images[i].buffer = (GrayScalePixelType*) malloc(imageSize*sizeof(GrayScalePixelType));
+        if(imageSeries->images[i].buffer == NULL) {
+            free(imageSeries->images);
+            free(imageSeries);
+            fclose(file);
+            return NULL;
+        }
         for (int j=0;j<imageSize;j++)
         {
             fread(&imageSeries->images[i].buffer[j],sizeof(GrayScalePixelType),1,file);
         }
         fread(&imageSeries->labels[i],sizeof(unsigned char),1,file);
      }
+    fclose(file);
 
     return imageSeries;
 }
@@ -52,6 +69,10 @@ GrayScaleImageSeries *readImages(const char *path)
 // TODO Vervollständigen Sie die Funktion clearSeries, welche eine Bildserie vollständig aus dem Speicher freigibt
 void clearSeries(GrayScaleImageSeries *series)
 {
+    for (int i = 0; i < series->count; i++)
+    {
+        free(series->images[i].buffer);
+    }
     free(series->images);
     free(series->labels);
     free(series);
diff --git a/matrix.c b/matrix.c
index ed849dc..5c7c0f2 100644
--- a/matrix.c
+++ b/matrix.c
@@ -70,7 +70,18 @@ MatrixType getMatrixAt(const Matrix matrix, unsigned int rowIdx, unsigned int co
 
 Matrix add(const Matrix matrix1, const Matrix matrix2)
 {
-    
+
+    //Prüfung ob größe Matrix1 und matrix2 identisch
+    Matrix matrix;
+    matrix.cols = matrix1.cols;
+    matrix.rows = matrix1.rows;
+    matrix.buffer= (MatrixType*) malloc(matrix.rows*matrix.cols * sizeof(MatrixType));
+    for (int i = 0; i < matrix1.rows; i++) {
+        for (int j = 0; j < matrix1.cols; j++) {
+           (matrix.buffer[i*matrix.cols+j])= (matrix1.buffer[i*matrix.cols+j]) + (matrix2.buffer[i*matrix.cols+j]);
+        }
+    }
+    return matrix;
 }
 
 Matrix multiply(const Matrix matrix1, const Matrix matrix2)
diff --git a/neuralNetworkTests.c b/neuralNetworkTests.c
index f5aa4be..477e342 100644
--- a/neuralNetworkTests.c
+++ b/neuralNetworkTests.c
@@ -8,6 +8,7 @@
 #define IDENTIFICATION_TAG "__info2_neural_network_file_format__"
 static void prepareNeuralNetworkFile(const char *path, const NeuralNetwork nn)
 {
+
 }
 
 void test_loadModelReturnsCorrectNumberOfLayers(void)