add update_dict task

practica/README.md

@@ -33,6 +33,7 @@ Among them there are:
         - [sum_num_nearby](stepik/stepik_tasks/sum_num_nearby.py)
         - [Sum of squared numbers](stepik/stepik_tasks/sum_of_squared_numbers.py)
         - [Tickets](stepik/stepik_tasks/tickets.py)
+        - [Function of updating dictionary](stepik/stepik_tasks/update_dictionary.py)
   
 
 

practica/stepik/README.md

@@ -28,5 +28,6 @@ different tasks from various courses
 - [sum_num_from_last](stepik_tasks/sum_num_from_last.py)
 - [sum_num_nearby](stepik_tasks/sum_num_nearby.py)
 - [Tickets](stepik_tasks/tickets.py)
+- [Function of updating dictionary](stepik_tasks/update_dictionary.py)
   
   

practica/stepik/stepik_tasks/README.md

@@ -61,3 +61,18 @@ __*Plan of solution*__:
 - [Tickets](tickets.py)
 
     A program that issues a “Lucky” or "regular" ticket, the number of which we entered. If all the numbers are the same - the ticket is lucky
+
+- [Function of updating dictionary](update_dictionary.py)
+
+    Function that searches the key in dictionary and in case key is exist append value, if it doesnt exist - searches key* 2 and update, if key* 2 doesnt exist too, so add it to the dictionary with value.
+
+    The coorect output:
+    ```python
+    d = {}
+    print(update_dictionary(d, 1, -1)) # None
+    print(d) # {2: [-1]}
+    update_dictionary(d, 2, -2)
+    print(d) # {2: [-1, -2]}
+    update_dictionary(d, 1, -3)
+    print(d) # {2: [-1, -2, -3]}
+    ```

practica/stepik/stepik_tasks/update_dictionary.py

@@ -0,0 +1,13 @@
+# function of update dict d
+d = {}
+def update_dictionary(d,key,value):
+    if key not in d:
+        new_key = int(key) *2
+        if new_key not in d:
+            d[new_key] = [value]
+        else: 
+            d[new_key] += [value]
+    else: 
+        d[key] += [value]
+
+