Bumblebee - Ellie Alavi

part-1.py

@@ -4,17 +4,46 @@
 # the appropriate comment.
 
 # factorial
-
+def factorial(n):
+    if n < 0:
+        raise ValueError("Input must be a non-negative integer.")
+    if n == 0:
+        return 1
+    return factorial(n-1) * n
 
 
 # reverse
-
-
+def reverse(text):
+    if len(text) <= 1:
+        return text
+    return reverse(text[1:]) + text[0]
 
 # bunny
+def bunny(count):
+    if count == 0:
+        return 0
+    return bunny(count-1) + 2
 
 
 
 # is_nested_parens
+def is_nested_parens(parens):
+    if len(parens) == 0:
+        return True
+
+    if parens[0] + parens[-1] != "()":
+        return False
+    return is_nested_parens(parens[1:-1])
+
+
+# Extra challenge:
+def is_nested_parens(parens):
+    return helper(parens, 0, len(parens) - 1)
 
+def helper(parens,left,right): # left and right are indices of first and last str char
+    if left > right:
+        return True
 
+    if parens[left] != "(" or parens[right] != ")":
+        return False
+    return helper(parens, left+1 , right-1)

part-2.py

@@ -4,13 +4,38 @@
 # the appropriate comment.
 
 # search
+def search(array,query):
+    if len(array) == 0:
+        return False
+
+    if array[0] == query:
+        return True
+    return search(array[1:],query)
 
 
 
 # is_palindrome
+def is_palindrome(text):
+    if len(text) == 0:
+        return True
+
+    if text[0] != text[-1]:
+        return False
+    return is_palindrome(text[1:-1])
 
 
 
 # digit_match
+def digit_match(int1, int2):
+    if int1 < 0 or int2 < 0:
+        raise ValueError("Input must be a non-negative integer.")
+
+    if int1 == 0 and int2 == 0:
+        return 1
+
+    match = 1 if (int1 % 10 == int2 % 10) else 0
 
+    if int1 < 10 or int2 < 10:
+        return match
 
+    return match + digit_match(int1 // 10, int2 // 10)