diff --git a/I2_Dobble/number.md b/I2_Dobble/number.md
index 4548262..305e726 100644
--- a/I2_Dobble/number.md
+++ b/I2_Dobble/number.md
@@ -1,4 +1,4 @@
-*createNumbers: 
+*createNumbers: -> numbers array gets filled with random entry with only one dublicate
 
 -> check if len is greater than 2
 -> create new array numbers, use malloc and check if correct
@@ -7,7 +7,10 @@
 -> 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[]
--> 
+-> stops at numbers[len -2]
+static dublicateRandomEntry:
+-> numbers[len-1] is filled with random already existing number
+-> numbers[len -1] gets switched with other random entry -> dublicate is placed randwom in entry; without the switch, dublicate would always be at the end
 
 
 getDublicate:
@@ -15,7 +18,7 @@ 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
+    -> simple loop to copy each element from numbers to 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
diff --git a/I2_Dobble/numbers.c b/I2_Dobble/numbers.c
index f3f23d2..8f6bda6 100644
--- a/I2_Dobble/numbers.c
+++ b/I2_Dobble/numbers.c
@@ -15,12 +15,10 @@ static void dublicateRandomEntry (unsigned int *numbers, unsigned int len)
 {
    if (numbers && len > 2)
    {
-        unsigned int dubIndx = rand() % len;
+        unsigned int dubIndx = rand() % (len - 1);
         unsigned int copyIndx;
         
-        do {
-            copyIndx = rand() % len;
-        } while (copyIndx == dubIndx);
+        copyIndx = rand() % len;
 
         numbers[len - 1] = numbers[dubIndx];