rewrite min_interval_search, rename to interval_search_lowest

Author: wojtask

src/chapter14/exercise14_3_3.py

@@ -1,17 +1,14 @@
-from chapter14.textbook14_3 import interval_search, overlap
+from chapter14.textbook14_3 import overlap
 
 
-def min_interval_search(T, i):
-    x = interval_search(T, i)
-    if x is not T.nil:
-        y = x.left
-        while y is not T.nil:
-            if overlap(i, y.int):
-                x = y
-                y = x.left
-            else:
-                if y.left is not T.nil and y.left.max >= i.low:
-                    y = y.left
-                else:
-                    y = y.right
-    return x
+def interval_search_lowest(T, i):
+    x = T.root
+    y = T.nil
+    while x is not T.nil:
+        if overlap(i, x.int) and (y is T.nil or x.int.low < y.int.low):
+            y = x
+        if x.left is not T.nil and x.left.max >= i.low:
+            x = x.left
+        else:
+            x = x.right
+    return y

test/test_chapter14/test_exercise14_3_3.py

@@ -3,7 +3,7 @@
 
 from hamcrest import *
 
-from chapter14.exercise14_3_3 import min_interval_search
+from chapter14.exercise14_3_3 import interval_search_lowest
 from chapter14.textbook14_3 import overlap
 from datastructures.array import Array
 from datastructures.essential import Interval
@@ -12,15 +12,15 @@
 
 class TestExercise14_3_3(TestCase):
 
-    def test_min_interval_search(self):
+    def test_interval_search_lowest(self):
         tree = get_random_interval_tree()
         inorder_nodes = get_binary_search_tree_inorder_nodes(tree)
         inorder_intervals = Array(node.int for node in inorder_nodes)
         low_endpoint = random.randint(0, 949)
         high_endpoint = low_endpoint + random.randint(0, 50)
         interval = Interval(low_endpoint, high_endpoint)
 
-        actual_found = min_interval_search(tree, interval)
+        actual_found = interval_search_lowest(tree, interval)
 
         if actual_found is not tree.nil:
             assert_that(overlap(actual_found.int, interval))