diff --git a/I2_Dobble/number.md b/I2_Dobble/number.md
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+*createNumbers: 
+
+-> check if len is greater than 2
+-> create new array numbers, use malloc and check if correct
+-> set seed for rand()
+-> create new TreeNode root
+-> add new value to tree using addToTree and rand()
+-> addToTree sets isDup to 1, if value already exists
+-> if value does not already exist -> add to numbers[]
+-> 
+
+
+getDublicate:
+
+-> numbers (Zeiger != NULL) und len (min. 2) check
+-> define new array numbersCopy
+-> copy numbers to numbersCopy 
+    -> simple loop to copy each element number -> numbersCopy
+-> sort numbersCopy with qsort
+-> compare each element of numbersCopy with next element (if numbersCopy[i] == numbersCopy[i+1] -> dublicate was found, because same values are right next to each other)
+-> return found dublicate
+
+compare:
+
+-> gibt 1 aus, wenn a größer ist
+-> gibt -1 aus, wenn b größer ist
+-> gibt 0 aus wenn a==b