diff --git a/.gitignore b/.gitignore
index fc53910..ca403e0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,6 @@ runNumbersTest.exe
 numbers.o
 .vscode/launch.json
 .vscode/settings.json
+*.o
+*.exe
+runBintreeTest
diff --git a/bintree.c b/bintree.c
index 552c170..9a50707 100644
--- a/bintree.c
+++ b/bintree.c
@@ -1,7 +1,10 @@
 #include <string.h>
+#include <stdio.h>
 #include "stack.h"
 #include "bintree.h"
 
+static StackNode *stack;
+static TreeNode *tree = NULL;
 // TODO: binären Suchbaum implementieren
 /*  * `addToTree`: fügt ein neues Element in den Baum ein (rekursiv),
  * `clearTree`: gibt den gesamten Baum frei (rekursiv),
@@ -12,8 +15,43 @@
 // if isDuplicate is NULL, otherwise ignores duplicates and sets isDuplicate to 1 (or to 0 if a new entry is added).
 TreeNode *addToTree(TreeNode *root, const void *data, size_t dataSize, CompareFctType compareFct, int *isDuplicate)
 {
+    if (root == NULL)
+    {
+        TreeNode *newNode = malloc(sizeof(TreeNode));
+        newNode->data = malloc(dataSize);
+        if (newNode->data == NULL)
+        {
+            return NULL; // Fehler
+        }
+        memcpy(newNode->data, data, dataSize);
+        newNode->left = NULL;
+        newNode->right = NULL;
+        return newNode;
+    }
     
+    int cmp = compareFct(root->data, data);
+    if (cmp < 0)
+    {
+        root->left = addToTree(root->left, data, dataSize, compareFct, isDuplicate);
+    }
+    else if (cmp > 0)
+    {
+        root->right = addToTree(root->right, data, dataSize, compareFct, isDuplicate);
+    }
+    else
+    {
+        if (isDuplicate != NULL)
+        {
+            *isDuplicate = 1;
+            return root;
+        }
+        else
+        {
+            root->left = addToTree(root->left, data, dataSize, compareFct, isDuplicate);
+        }
+    }
 
+    return root;
 }
 
 // Iterates over the tree given by root. Follows the usage of strtok. If tree is NULL, the next entry of the last tree given is returned in ordering direction.
@@ -21,7 +59,19 @@ TreeNode *addToTree(TreeNode *root, const void *data, size_t dataSize, CompareFc
 // push the top node and push all its left nodes.
 void *nextTreeData(TreeNode *root)
 {
+    if (root != NULL)
+    {
+        clearStack(stack);
+        buildStack(root);
+    }
+    if(stack != NULL)
+    {
+        void* data = top(stack);
+        stack = pop(stack);
+        return data;
+    }
 
+    return NULL;
 }
 
 // Releases all memory resources (including data copies).
@@ -31,32 +81,34 @@ void clearTree(TreeNode *root)
     {
         return;
     }
-    
     if (root->left != NULL)
     {
         clearTree(root->left);
         free(root->left);
+        root->left = NULL;
     }
-    else if (root->right != NULL)
+    if (root->right != NULL)
     {
         clearTree(root->right);
         free(root->right);
+        root->right = NULL;
     }
-    root->data = NULL;
+    root = NULL;
 }
 
 // Returns the number of entries in the tree given by root.
 unsigned int treeSize(const TreeNode *root)
 {
-    int counterL, counterR = 0;
-    if (root->left != NULL)
-    {
-        counterL = treeSize(root->left) + 1;
-    }
-    else if (root->right != NULL)
-    {
-        counterR = treeSize(root->right) + 1;
-    }
+    return root == NULL ? 0 : treeSize(root->left) + treeSize(root->right) + 1;
+}
 
-    return counterL + counterR;
+void buildStack(TreeNode *root)
+{
+    if (root == NULL)
+    {
+       return; 
+    }
+    buildStack(root->left);
+    stack = push(stack, root->data);
+    buildStack(root->right); 
 }
\ No newline at end of file
diff --git a/bintree.h b/bintree.h
index 25e16b2..f7be496 100644
--- a/bintree.h
+++ b/bintree.h
@@ -24,4 +24,6 @@ void clearTree(TreeNode *root);
 // Returns the number of entries in the tree given by root.
 unsigned int treeSize(const TreeNode *root);
 
+void buildStack(TreeNode *root);
+
 #endif
\ No newline at end of file
diff --git a/highscore.c b/highscore.c
index fe8a458..8d3ef5c 100644
--- a/highscore.c
+++ b/highscore.c
@@ -79,6 +79,8 @@ int addHighscore(const char *name, double timeInSeconds, unsigned int len)
 {
     HighscoreEntry entry = createHighscoreEntry(name, calculateScore(timeInSeconds, len));
     highscoreTree = addToTree(highscoreTree, &entry, sizeof(entry), compareHighscoreEntries, NULL);
+    //HighscoreEntry *temp = highscoreTree->data;
+    //printf("%s%d\n", temp->name, temp->score);
 
     return entry.score;
 }
diff --git a/highscores.txt b/highscores.txt
index 4edd5a7..d1dcaac 100644
--- a/highscores.txt
+++ b/highscores.txt
@@ -1 +1,5 @@
-player1;3999
+nick;9963
+nick;9946
+simon;4965
+alex;2996
+simon;2996
diff --git a/makefile b/makefile
index fdb61da..d439d9a 100644
--- a/makefile
+++ b/makefile
@@ -35,14 +35,20 @@ $(program_obj_filesobj_files): %.o: %.c
 # --------------------------
 # Unit Tests
 # --------------------------
-unitTests: stack.o test_stack.c $(unityfolder)/unity.c
+stackTests: stack.o test_stack.c $(unityfolder)/unity.c
 	$(CC) $(FLAGS) -I$(unityfolder) -o runStackTest test_stack.c stack.o $(unityfolder)/unity.c
 
 # --------------------------
 # numbers.c Tests
 # --------------------------
-numbersTests: numbers.o test_numbers.c $(unityfolder)/unity.c
-	$(CC) $(FLAGS) -I$(unityfolder) -o runNumbersTest test_numbers.c numbers.o $(unityfolder)/unity.c
+numbersTests: numbers.o bintree.o stack.o test_numbers.c $(unityfolder)/unity.c
+	$(CC) $(FLAGS) -I$(unityfolder) -o runNumbersTest test_numbers.c numbers.o bintree.o stack.o $(unityfolder)/unity.c
+
+# --------------------------
+# bintree.c Tests
+# --------------------------
+bintreeTests: bintree.o stack.o test_bintree.c $(unityfolder)/unity.c
+	$(CC) $(FLAGS) -I$(unityfolder) -o runBintreeTest test_bintree.c bintree.o stack.o $(unityfolder)/unity.c
 
 # --------------------------
 # Clean
diff --git a/numbers.c b/numbers.c
index 41d0980..90e930a 100644
--- a/numbers.c
+++ b/numbers.c
@@ -14,150 +14,97 @@
 // Returns len random numbers between 1 and 2x len in random order which are all different, except for two entries.
 // Returns NULL on errors. Use your implementation of the binary search tree to check for possible duplicates while
 // creating random numbers.
-unsigned int checkArray(unsigned int *array, unsigned int len, unsigned int number)
+void duplicateNumber(unsigned int *numbers, unsigned int len)
 {
-  int free = 1;
+  if (!numbers || len < 2)
+    return;
 
-  for (int i = 0; i < len; i++)
-  {
-    if (array[i] == number)
-    {
-      free = 0;
-    }
-  }
+  unsigned int numberPicked = rand() % len; // take random spot in array
+  unsigned int destination = rand() % len;  // new spot for duplicated number
 
-  return free;
+  while (destination == numberPicked) // while same spot get a new one
+    destination = rand() % len;
+
+  numbers[destination] = numbers[numberPicked];
+}
+
+/* for qsort
+-1	  num1 should come before num2
+0	    num1 and num2 are equal
+1	    num1 should come after num2
+*/
+int compare(const void *num1, const void *num2)
+{
+  unsigned int temp1 = *(const unsigned int *)num1;
+  unsigned int temp2 = *(const unsigned int *)num2;
+  return (temp1 > temp2) - (temp1 < temp2);
 }
 
 unsigned int *createNumbers(unsigned int len)
 {
-  srand(time(NULL));
-  unsigned int *array = (unsigned int*)malloc(len * sizeof(unsigned int));
-  int randomNr, counter;
+  if (len < 2)
+  {
+    return NULL;
+  }
+  srand((unsigned)time(NULL));
 
-  if(array == NULL)
+  TreeNode *root = NULL;
+  unsigned int i = 0;
+
+  unsigned int *numbers = malloc(sizeof(unsigned int) * len);
+  if (!numbers)
   {
     return NULL;
   }
 
-  for (int i = 0; i < len; i++)
+  while (i < len)
   {
-    counter = 0;
-    do
+    unsigned int random = (rand() % (2 * len)) + 1;
+    int duplicate = 0;
+
+    root = addToTree(root, &random, sizeof(unsigned int), compare, &duplicate);
+    if (!root)
     {
-      if (counter == 9)
-      {
-        return NULL;
-      }
-      
-      randomNr = rand() % (2 * len + 1);
-      counter++;
-    } while (!checkArray(array, i, randomNr));
-
-    array[i] = randomNr;
-    printf("%u ", array[i]);
-  }
-
-  printf("\n");
-  return array;
-}
-
-void merge(unsigned int arr[], unsigned int left, unsigned int mid, unsigned int right)
-{
-  unsigned int i, j, k;
-  unsigned int n1 = mid - left + 1;
-  unsigned int n2 = right - mid;
-
-  // Create temporary arrays
-  unsigned int leftArr[n1], rightArr[n2];
-
-  // Copy data to temporary arrays
-  for (i = 0; i < n1; i++)
-    leftArr[i] = arr[left + i];
-  for (j = 0; j < n2; j++)
-    rightArr[j] = arr[mid + 1 + j];
-
-  // Merge the temporary arrays back into arr[left..right]
-  i = 0;
-  j = 0;
-  k = left;
-  while (i < n1 && j < n2)
-  {
-    if (leftArr[i] <= rightArr[j])
-    {
-      arr[k] = leftArr[i];
-      i++;
+      free(numbers); // malloc-Fehler
+      return NULL;
     }
-    else
-    {
-      arr[k] = rightArr[j];
-      j++;
-    }
-    k++;
+
+    if (!duplicate)
+      numbers[i++] = random;
   }
 
-  // Copy the remaining elements of leftArr[], if any
-  while (i < n1)
-  {
-    arr[k] = leftArr[i];
-    i++;
-    k++;
-  }
-
-  // Copy the remaining elements of rightArr[], if any
-  while (j < n2)
-  {
-    arr[k] = rightArr[j];
-    j++;
-    k++;
-  }
+  duplicateNumber(numbers, len);
+  clearTree(root);
+  return numbers;
 }
 
-void mergeSort(unsigned int arr[], unsigned int left, unsigned int right)
-{
-  if (left < right)
-  {
-
-    // Calculate the midpoint
-    unsigned int mid = left + (right - left) / 2;
-
-    // Sort first and second halves
-    mergeSort(arr, left, mid);
-    mergeSort(arr, mid + 1, right);
-
-    // Merge the sorted halves
-    merge(arr, left, mid, right);
-  }
-}
-
-// Returns only the only number in numbers which is present twice. Returns zero on errors.
+// Returns the only number in numbers which is present twice. Returns zero on errors.
 unsigned int getDuplicate(const unsigned int numbers[], unsigned int len)
 {
-  unsigned int temp[len];
-  unsigned int duplicate = 0;
-
-  /*if(numbers == NULL || (sizeof(numbers) / sizeof(typeof(numbers)) != len))
+  if (!numbers || len < 2)
   {
-    return 0;S
-  }*/
-
-  for (int i = 0; i < len; i++)
-  {
-    temp[i] = numbers[i];
+    return 0;
   }
-  
-  // Sorting arr using mergesort
-  mergeSort(temp, 0, len - 1);
 
-  for (int i = 0; i < len - 1; i++)
+  unsigned int *copy = (unsigned int *)malloc(len * sizeof(unsigned int));
+  if (!copy)
   {
-    duplicate = temp[i];
-    if (duplicate == temp[i + 1])
+    return 0;
+  }
+
+  memcpy(copy, numbers, len * sizeof(unsigned int));
+  qsort(copy, len, sizeof(unsigned int), compare);
+
+  unsigned int duplicate = 0;
+  for (unsigned int i = 1; i < len; i++)
+  {
+    if (copy[i] == copy[i - 1])
     {
-      
+      duplicate = copy[i];
       break;
     }
   }
 
+  free(copy);
   return duplicate;
 }
\ No newline at end of file
diff --git a/numbers.o b/numbers.o
deleted file mode 100644
index 2b1174a..0000000
Binary files a/numbers.o and /dev/null differ
diff --git a/runNumbersTest.exe b/runNumbersTest.exe
deleted file mode 100644
index 8b78d8f..0000000
Binary files a/runNumbersTest.exe and /dev/null differ
diff --git a/stack.c b/stack.c
index 2315722..8762fa3 100644
--- a/stack.c
+++ b/stack.c
@@ -10,46 +10,24 @@
 // 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;
+    StackNode *newNode = malloc(sizeof(StackNode));
+    newNode->data = data;
+    newNode->next = stack;  // Set the new node's next pointer to the current top of the stack.
+    return newNode;  // Return the new node as the top of the 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;
+        return NULL;  // Nothing to pop if stack is empty.
     }
 
-    tempNode = stack;
-    while (tempNode->next->next != NULL)
-    {
-        tempNode = tempNode->next;
-    }
-    free(tempNode->next);
-    tempNode->next = NULL;
+    StackNode *tempNode = stack;
+    stack = stack->next;  // Move the stack pointer to the next node.
+    free(tempNode);  // Free the old top node.
 
     return stack;
 }
@@ -57,35 +35,19 @@ StackNode *pop(StackNode *stack)
 // Returns the data of the top element.
 void *top(StackNode *stack)
 {
-    StackNode *tempNode;
-
     if (stack == NULL)
     {
-        return NULL;
+        return NULL;  // Return NULL if stack is empty.
     }
 
-    tempNode = stack;
-    while (tempNode->next != NULL)
-    {
-        tempNode = tempNode->next;
-    }
-
-    return &tempNode->value;
+    return stack->data;  // Return the value of the top node.
 }
 
 // Clears stack and releases all memory.
 void clearStack(StackNode *stack)
 {
-    StackNode *tempNode;
-
-    if (stack == NULL)
+    while (stack != NULL)
     {
-        return;
-    }
-
-    tempNode = stack;
-    while (tempNode != NULL)
-    {
-        tempNode = pop(tempNode);
+        stack = pop(stack);  // Pop each element and free memory.
     }
 }
\ No newline at end of file
diff --git a/stack.h b/stack.h
index d7cc86a..69ac923 100644
--- a/stack.h
+++ b/stack.h
@@ -9,7 +9,7 @@ The latest element is taken from the stack. */
 
 //TODO: passenden Datentyp als struct anlegen
 typedef struct Node {
-    int value;
+    void *data;
     struct Node* next;
 } StackNode;
 
diff --git a/test_bintree.c b/test_bintree.c
new file mode 100644
index 0000000..b5daa3a
--- /dev/null
+++ b/test_bintree.c
@@ -0,0 +1,80 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "bintree.h"
+#include "unity.h"
+
+
+void sizeTest()
+{
+    TreeNode *root = (TreeNode *)malloc(sizeof(TreeNode));
+    TreeNode *node1 = (TreeNode *)malloc(sizeof(TreeNode));
+    TreeNode *node2 = (TreeNode *)malloc(sizeof(TreeNode));
+
+    int dataRoot = 2;
+    int dataNode1 = 1;
+    int dataNode2 = 3;
+
+    root->data = &dataRoot;
+    root->left = (TreeNode *)node1;
+    root->right = (TreeNode *)node2;
+
+    node1->data = &dataNode1;
+    node1->left = NULL;
+    node1->right = NULL;
+
+    node2->data = &dataNode2;
+    node2->left = NULL;
+    node2->right = NULL;
+
+    TEST_ASSERT_EQUAL_INT(3,treeSize(root));
+}
+
+void clearTest()
+{
+    TreeNode *root = (TreeNode *)malloc(sizeof(TreeNode));
+    TreeNode *node1 = (TreeNode *)malloc(sizeof(TreeNode));
+    TreeNode *node2 = (TreeNode *)malloc(sizeof(TreeNode));
+
+    int dataRoot = 2;
+    int dataNode1 = 1;
+    int dataNode2 = 3;
+
+    root->data = &dataRoot;
+    root->left = (TreeNode *)node1;
+    root->right = (TreeNode *)node2;
+
+    node1->data = &dataNode1;
+    node1->left = NULL;
+    node1->right = NULL;
+
+    node2->data = &dataNode2;
+    node2->left = NULL;
+    node2->right = NULL;
+
+    clearTree(root);
+    root = NULL;
+
+    TEST_ASSERT_EQUAL_INT(0,treeSize(root));
+}
+
+void setUp(void)
+{
+    // Falls notwendig, kann hier Vorbereitungsarbeit gemacht werden
+}
+
+void tearDown(void)
+{
+    // Hier kann Bereinigungsarbeit nach jedem Test durchgeführt werden
+}
+
+int main()
+{
+    UNITY_BEGIN();
+
+    printf("============================\nNumbers tests\n============================\n");
+
+    RUN_TEST(sizeTest);
+    RUN_TEST(clearTest);
+
+    return UNITY_END();
+}
\ No newline at end of file
diff --git a/test_numbers.c b/test_numbers.c
index 04b5069..f98a45f 100644
--- a/test_numbers.c
+++ b/test_numbers.c
@@ -3,26 +3,47 @@
 #include "numbers.h"
 #include "unity.h"
 
-void createNumbersTest()
+void test_createNumbers() 
 {
-    unsigned int *array;
     unsigned int len = 6;
-
-    array = createNumbers(len);
-    for (int i = 0; i < len; i++)
-    {
-        printf("%u ", array[i]);
-    }
-    printf("\n");
+    unsigned int *array = createNumbers(len);
     TEST_ASSERT_NOT_NULL(array);
+
+    unsigned int duplicate = getDuplicate(array, len);
+    TEST_ASSERT_NOT_EQUAL(0, duplicate);
+
+    int counter = 0;
+    for (unsigned int i = 0; i < len; i++) 
+    {
+        if (array[i] == duplicate) 
+            counter++;
+    }
+    
+    TEST_ASSERT_EQUAL(2, counter);
+
+    free(array);
 }
 
-void duplicateTest()
+void test_createNumbers_values()
 {
-    unsigned int array[6] = {1, 4, 5, 2, 3, 1};
     unsigned int len = 6;
+    unsigned int *array = createNumbers(len);
+    TEST_ASSERT_NOT_NULL(array);
 
-    TEST_ASSERT_EQUAL_INT(1, getDuplicate(array, len));
+    for (unsigned int i = 0; i < len; i++)
+    {
+        TEST_ASSERT_TRUE(array[i] >= 1);
+        TEST_ASSERT_TRUE(array[i] <= 2 * len);
+    }
+
+    free(array);
+}
+
+void test_getDuplicate() 
+{
+    unsigned int array[6] = {1, 2, 4, 4, 6, 7};
+    unsigned int duplicate = getDuplicate(array, 6);
+    TEST_ASSERT_EQUAL_UINT(4, duplicate);
 }
 
 void setUp(void)
@@ -35,13 +56,15 @@ void tearDown(void)
     // Hier kann Bereinigungsarbeit nach jedem Test durchgeführt werden
 }
 
-int main()
+int main() 
 {
     UNITY_BEGIN();
 
-    printf("============================\nNumbers tests\n============================\n");
-    RUN_TEST(createNumbersTest);
-    RUN_TEST(duplicateTest);
+    printf("\n============================\n Numbers tests\n============================\n");
+
+    RUN_TEST(test_createNumbers);
+    RUN_TEST(test_createNumbers_values);
+    RUN_TEST(test_getDuplicate);
 
     return UNITY_END();
 }
\ No newline at end of file
diff --git a/test_stack.c b/test_stack.c
index 2e59a8f..874e5f7 100644
--- a/test_stack.c
+++ b/test_stack.c
@@ -3,16 +3,33 @@
 #include "stack.h"
 #include "unity.h"
 
-void test_push(void)
+void test_push(void) {
+    StackNode *stack = NULL;
+    int data1 = 10, data2 = 20;
+
+    // Push elements to the stack
+    stack = push(stack, &data1);
+    stack = push(stack, &data2);
+
+    // Check if the stack is not empty
+    TEST_ASSERT_NOT_NULL(stack);
+
+    // Check if the top element is correct
+    int *topData = top(stack);
+    TEST_ASSERT_EQUAL_INT(20, *topData);  // The last pushed element should be on top
+}
+
+void test_push1(void)
 {
-    StackNode *testNode;
+    StackNode *testNode = NULL;
     int data = 1;
 
     // Test für leeren Stack
-    testNode = push(NULL, &data);
+    testNode = push(testNode, &data);
     TEST_ASSERT_NOT_NULL(&testNode);
     TEST_ASSERT_NULL(testNode->next);
-    TEST_ASSERT_EQUAL_INT(1, testNode->value);
+    int *temp = testNode->data;
+    TEST_ASSERT_EQUAL_INT(1, *temp);
 
     data = 2;
 
@@ -21,26 +38,53 @@ void test_push(void)
     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);
+    temp = testNode->data;
+    TEST_ASSERT_EQUAL_INT(2, *temp);
+    testNode = testNode->next;
+    temp = testNode->data;
+    TEST_ASSERT_EQUAL_INT(1, *temp);
 }
 
-StackNode* setup(int value, StackNode* next) {
+StackNode* setup(void *data, StackNode* next) {
     StackNode* node = malloc(sizeof(StackNode)); // allocate memory on heap
     if (node == NULL) {
         perror("malloc failed");
         exit(EXIT_FAILURE); // or handle the error differently
     }
-    node->value = value;
+    node->data = data;
     node->next = next;
     return node;
 }
+void test_pop(void) {
+    StackNode *stack = NULL;
+    int data1 = 10, data2 = 20;
 
-void test_pop(void)
+    // Push elements to the stack
+    stack = push(stack, &data1);
+    stack = push(stack, &data2);
+
+    // Pop the top element
+    stack = pop(stack);
+
+    // Check if the top element is now the first pushed element
+    int *topData = top(stack);
+    TEST_ASSERT_EQUAL_INT(10, *topData);  // After popping, the first element should be on top
+
+    // Pop the last element
+    stack = pop(stack);
+
+    // Check if the stack is empty now
+    TEST_ASSERT_NULL(stack);  // Stack should be NULL now
+}
+void test_pop2(void)
 {   
-    StackNode* node2 = setup(3, NULL);
-    StackNode* node1 = setup(2, node2);
-    StackNode* header = setup(1, node1);
+    int x,y,z;
+    x = 1;
+    y = 2;
+    z = 3;
+    StackNode* node2 = setup(&z, NULL);
+    StackNode* node1 = setup(&y, node2);
+    StackNode* header = setup(&x, node1);
     StackNode* temp;
 
     temp = pop(header);
@@ -56,35 +100,36 @@ void test_pop(void)
     TEST_ASSERT_NULL(node1->next);
 }
 
-void test_top(void)
-{
-    StackNode* node2 = setup(3, NULL);
-    StackNode* node1 = setup(2, node2);
-    StackNode* header = setup(1, node1);
+void test_top(void) {
+    StackNode *stack = NULL;
+    int data1 = 10, data2 = 20;
 
-    int data = *(int *)top(header);
-    TEST_ASSERT_EQUAL_INT(node2->value, data);
+    // Push elements to the stack
+    stack = push(stack, &data1);
+    stack = push(stack, &data2);
+
+    // Check the top element
+    int *topData = top(stack);
+    TEST_ASSERT_EQUAL_INT(20, *topData);  // The top element should be 20 (last pushed)
+
+    // Pop the top element and check the new top
+    stack = pop(stack);
+    topData = top(stack);
+    TEST_ASSERT_EQUAL_INT(10, *topData);  // Now the top element should be 10
 }
 
-void test_clear()
+void test_top2(void)
 {
-    StackNode* node2 = setup(3, NULL);
-    StackNode* node1 = setup(2, node2);
-    StackNode* header = setup(1, node1);
-    StackNode* temp;
-    
-    clearStack(header);
-    temp = header;
-    
-    int after = 0;
-    while(temp) 
-    {
-        after++;
-        temp = temp->next;
-    }
+    int x,y,z;
+    x = 1;
+    y = 2;
+    z = 3;
+    StackNode* node2 = setup(&z, NULL);
+    StackNode* node1 = setup(&y, node2);
+    StackNode* header = setup(&x, node1);
 
-    
-    TEST_ASSERT_NULL(after);
+    int data = *(int *)top(header);
+    TEST_ASSERT_EQUAL_INT(node2->data, data);
 }
 
 void setUp(void)
@@ -106,7 +151,6 @@ int main()
     RUN_TEST(test_push);
     RUN_TEST(test_pop);
     RUN_TEST(test_top);
-    RUN_TEST(test_clear);
 
     return UNITY_END();
 }
\ No newline at end of file