diff --git a/stack.c b/stack.c
index 5bfb882..2315722 100644
--- a/stack.c
+++ b/stack.c
@@ -1,91 +1,91 @@
-#include <stdlib.h>
-#include "stack.h"
-
-// TODO: grundlegende Stackfunktionen implementieren:
-/*  * `push`: legt ein Element oben auf den Stack,
- * `pop`: entfernt das oberste Element,
- * `top`: liefert das oberste Element zurück,
- * `clearStack`: gibt den gesamten Speicher frei. */
-
-// Pushes data as pointer onto the stack.
-StackNode *push(StackNode *stack, void *data)
-{
-    StackNode *tempNode, *newNode;
-
-    newNode = malloc(sizeof(StackNode));
-    newNode->value = 3;
-    newNode->next = NULL;
-
-    if (stack == NULL)
-    {
-        stack = newNode;
-        return stack;
-    }
-
-    tempNode = stack;
-    while (tempNode->next != NULL)
-    {
-        tempNode = tempNode->next;
-    }
-    tempNode->next = newNode;
-
-    return stack;
-}
-
-// Deletes the top element of the stack (latest added element) and releases its memory. (Pointer to data has to be
-// freed by caller.)
-StackNode *pop(StackNode *stack)
-{
-    StackNode *tempNode;
-
-    if (stack == NULL)
-    {
-        return stack;
-    }
-
-    tempNode = stack;
-    while (tempNode->next->next != NULL)
-    {
-        tempNode = tempNode->next;
-    }
-    free(tempNode->next);
-    tempNode->next = NULL;
-
-    return stack;
-}
-
-// Returns the data of the top element.
-void *top(StackNode *stack)
-{
-    StackNode *tempNode;
-
-    if (stack == NULL)
-    {
-        return NULL;
-    }
-
-    tempNode = stack;
-    while (tempNode->next != NULL)
-    {
-        tempNode = tempNode->next;
-    }
-
-    return &tempNode->value;
-}
-
-// Clears stack and releases all memory.
-void clearStack(StackNode *stack)
-{
-    StackNode *tempNode;
-
-    if (stack == NULL)
-    {
-        return;
-    }
-
-    tempNode = stack;
-    while (tempNode != NULL)
-    {
-        tempNode = pop(tempNode);
-    }
+#include <stdlib.h>
+#include "stack.h"
+
+// TODO: grundlegende Stackfunktionen implementieren:
+/*  * `push`: legt ein Element oben auf den Stack,
+ * `pop`: entfernt das oberste Element,
+ * `top`: liefert das oberste Element zurück,
+ * `clearStack`: gibt den gesamten Speicher frei. */
+
+// Pushes data as pointer onto the stack.
+StackNode *push(StackNode *stack, void *data)
+{
+    StackNode *tempNode, *newNode;
+
+    newNode = malloc(sizeof(StackNode));
+    newNode->value = *(int *)data;
+    newNode->next = NULL;
+
+    if (stack == NULL)
+    {
+        stack = newNode;
+        return stack;
+    }
+
+    tempNode = stack;
+    while (tempNode->next != NULL)
+    {
+        tempNode = tempNode->next;
+    }
+    tempNode->next = newNode;
+
+    return stack;
+}
+
+// Deletes the top element of the stack (latest added element) and releases its memory. (Pointer to data has to be
+// freed by caller.)
+StackNode *pop(StackNode *stack)
+{
+    StackNode *tempNode;
+
+    if (stack == NULL)
+    {
+        return stack;
+    }
+
+    tempNode = stack;
+    while (tempNode->next->next != NULL)
+    {
+        tempNode = tempNode->next;
+    }
+    free(tempNode->next);
+    tempNode->next = NULL;
+
+    return stack;
+}
+
+// Returns the data of the top element.
+void *top(StackNode *stack)
+{
+    StackNode *tempNode;
+
+    if (stack == NULL)
+    {
+        return NULL;
+    }
+
+    tempNode = stack;
+    while (tempNode->next != NULL)
+    {
+        tempNode = tempNode->next;
+    }
+
+    return &tempNode->value;
+}
+
+// Clears stack and releases all memory.
+void clearStack(StackNode *stack)
+{
+    StackNode *tempNode;
+
+    if (stack == NULL)
+    {
+        return;
+    }
+
+    tempNode = stack;
+    while (tempNode != NULL)
+    {
+        tempNode = pop(tempNode);
+    }
 }
\ No newline at end of file
diff --git a/test_stack.c b/test_stack.c
index 2acb342..2e59a8f 100644
--- a/test_stack.c
+++ b/test_stack.c
@@ -3,6 +3,28 @@
 #include "stack.h"
 #include "unity.h"
 
+void test_push(void)
+{
+    StackNode *testNode;
+    int data = 1;
+
+    // Test für leeren Stack
+    testNode = push(NULL, &data);
+    TEST_ASSERT_NOT_NULL(&testNode);
+    TEST_ASSERT_NULL(testNode->next);
+    TEST_ASSERT_EQUAL_INT(1, testNode->value);
+
+    data = 2;
+
+    // Test für nicht leeren Stack
+    testNode = push(testNode, &data);
+    TEST_ASSERT_NOT_NULL(&testNode);
+    TEST_ASSERT_NOT_NULL(testNode->next);
+    TEST_ASSERT_NULL(testNode->next->next);
+    TEST_ASSERT_EQUAL_INT(1, testNode->value);
+    TEST_ASSERT_EQUAL_INT(2, testNode->next->value);
+}
+
 StackNode* setup(int value, StackNode* next) {
     StackNode* node = malloc(sizeof(StackNode)); // allocate memory on heap
     if (node == NULL) {
@@ -81,6 +103,7 @@ int main()
 
     printf("============================\nStack tests\n============================\n");
 
+    RUN_TEST(test_push);
     RUN_TEST(test_pop);
     RUN_TEST(test_top);
     RUN_TEST(test_clear);