Yekaterina Galochkina Bumblebee

part-1.py

@@ -5,16 +5,41 @@
 
 # factorial
 
+def factorial(n):
+    if n < 0:
+        raise ValueError("Factorial is not defined for negative numbers")
+    if n <= 1:
+        return 1
+    return n * factorial(n - 1)
 
 
 # reverse
 
+def reverse(text):
+    if not text:
+        return ''
+    return text[-1] + reverse(text[:-1])
 
 
 # bunny
 
+def bunny(count):
+    if count == 0:
+        return 0
+    return 2 + bunny(count - 1)
 
 
 # is_nested_parens
 
+def is_nested_parens(parens):
+    if not parens:
+        return True
+    try:
+        x = parens.index('(')
+        y = parens.index(')')
+        new_s = parens[:x] + parens[x+1:y] + parens[y+1:]
+        return is_nested_parens(new_s)
+    except ValueError:
+        return False
+
 

part-2.py

@@ -5,12 +5,39 @@
 
 # search
 
+def search(array, query):
+    if not array:
+        return False
+    if array[0] == query:
+        return True
+    else:
+        del array[0]
+        return search(array, query)
 
 
 # is_palindrome
 
+def is_palindrome(text):
+    if len(text) == 0:
+        return False
+    if len(text) == 1:
+        return True
+    if text[0] == text[-1]:
+        text = text[1:]
+        text = text[:-1]
+        return is_palindrome(text)
 
 
 # digit_match
 
-
+def digit_match(num1,num2):
+    if not len(str(num1)) or not len(str(num2)):
+        return 0
+
+    first = str(num1)[:-1]
+    second = str(num2)[:-1]
+
+    if str(num1)[-1] == str(num2)[-1]:
+        return 1 + digit_match(first, second)
+    else:
+        return 0 + digit_match(first, second)