add some int-cake problems

Author: Mia von Steinkirch

interview_cake/merge_sorted_list.py

@@ -0,0 +1,50 @@
+"""
+In order to win the prize for most cookies sold, my friend Alice and 
+# I are going to merge our Girl Scout Cookies orders and enter as one unit.
+# Each order is represented by an "order id" (an integer).
+We have our lists of orders sorted numerically already, in lists. 
+Write a function to merge our lists of orders into one sorted list.
+"""
+
+def merge_lists(my_list, alices_list):
+
+    result = []
+    index_alice_list = 0
+    index_my_list = 0
+
+    while index_alice_list < len(alices_list) and index_my_list < len(my_list):
+        if alices_list[index_alice_list] < my_list[index_my_list]:
+            result.append(alices_list[index_alice_list])
+            index_alice_list += 1
+        elif alices_list[index_alice_list] > my_list[index_my_list]:
+            result.append(my_list[index_my_list])
+            index_my_list += 1
+        else:
+            result.append(my_list[index_my_list])
+            result.append(alices_list[index_alice_list])
+            index_my_list += 1
+            index_alice_list += 1
+    
+    if index_alice_list < len(alices_list):
+        result.extend(alices_list[index_alice_list:])
+    
+    if index_my_list < len(my_list):
+        result.extend(my_list[index_my_list:])
+            
+    return result
+
+
+my_list     = [3, 4, 6, 10, 11, 15]
+alices_list = [1, 5, 8, 12, 14, 19]
+
+
+print merge_lists(my_list, alices_list)
+print "Must be [1, 3, 4, 5, 6, 8, 10, 11, 12, 14, 15, 19]"
+
+
+# Or just using Timsort
+def merge_sorted_lists(arr1, arr2):
+    return sorted(arr1 + arr2)
+
+print merge_sorted_lists(my_list, alices_list)
+print "Must be [1, 3, 4, 5, 6, 8, 10, 11, 12, 14, 15, 19]"

interview_cake/palindrome.py

@@ -0,0 +1,23 @@
+"""
+Write an efficient function that checks whether 
+any permutation of an input string is a palindrome.
+"""
+
+def has_palindrome_permutation(the_string):
+    unpaired_characters = set()
+
+    for char in the_string:
+        if char in unpaired_characters:
+            unpaired_characters.remove(char)
+        else:
+            unpaired_characters.add(char)
+
+    return len(unpaired_characters) <= 1
+
+str1 = "civic"
+print has_palindrome_permutation(str1)
+print "Should be True"
+
+str2 = "ivilc"
+print has_palindrome_permutation(str2)
+print "Should be False"

interview_cake/reverse_in_place.py

@@ -0,0 +1,13 @@
+# Write a function that takes a list of characters and reverses the letters in place.
+# O(n) time and O(1)O(1) space.
+
+def reverse_in_place(char_list):
+    return char_list[::-1]
+
+
+char_list = ['a', 'b', 'c', 'd', 'e', 'f']
+
+
+
+print(char_list)
+print(reverse_in_place(char_list))