Dragonflies C23 - Jane K.

part-1.py

@@ -4,17 +4,37 @@
 # the appropriate comment.
 
 # factorial
-
-
+def factorial(n):
+    if n < 0:
+        raise ValueError("Input must be >= 0.")
+    if n == 0:
+        return 1
+    return n * factorial(n - 1)
 
 # reverse
-
-
+def reverse(text):
+    # return text[::-1]
+
+    if text == "":
+        return ""  # base case
+
+    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 parens == "":
+        return True  # base case
+
+    if parens[0] == '(' and parens[-1] == ')':
+        return is_nested_parens(parens[1:-1])
+
+    return False

part-2.py

@@ -4,13 +4,47 @@
 # the appropriate comment.
 
 # search
-
-
+def search(array, query):
+
+    '''
+    I: array - usorted array of strings; query - string value to find
+    O: True - if query in array, False otherwise
+    '''
+    if not array:
+        return False
+
+    if array[0] == query:
+        return True
+
+    return search(array[1:], query)
 
 # is_palindrome
-
+def is_palindrome(text):
+    if len(text) <= 1:
+        return True
+
+    if text[0] != text[-1]:
+        return False
+
+    return is_palindrome(text[1:-1])
 
 
 # digit_match
-
-
+def digit_match(apples, oranges):
+    if apples == 0 and oranges == 0:
+        return 1
+    # If one or both are 1-digit numbers
+    elif apples < 10 or oranges < 10:
+        if apples % 10 == oranges % 10:
+            return 1
+
+        return 0
+
+    last_digit_apples = apples % 10
+    last_digit_oranges = oranges % 10
+
+    match = 0
+    if last_digit_apples == last_digit_oranges:
+        match = 1
+
+    return match + digit_match(apples // 10, oranges // 10)