11.3 fix

chapter_11/11.3.py

@@ -2,34 +2,34 @@
 CCC 11.3: Given a sorted array of n integers that have been rotated
 write code to find an element in the array.
 '''
-def modified_binary_search(rotated_array, element):
+def modified_binary_search(rotated_array, element, verbose=False):
     '''
     Modified Binary Search
     '''
     middle = len(rotated_array)/2
     middle_element = rotated_array[middle]
     left_slice = rotated_array[:middle]
-    right_slice = rotated_array[middle+1:]
-    print left_slice, right_slice
+    right_slice = rotated_array[middle:]
+    if verbose: print left_slice, right_slice
     if left_slice[0] <= middle_element:
         ''' Left slice is in order'''
-        print "Left Slice"
+        if verbose: print "Left Slice"
         trigger = False
         in_order = left_slice
         other_slice = right_slice
     else:
         '''Right side in order'''
-        print "Right Slice"
+        if verbose: print "Right Slice"
         trigger = True
         in_order = right_slice
         other_slice = left_slice
     if in_order[0] <= element and in_order[-1] >= element:
-        print "Reg Binary Search"
+        if verbose: print "Reg Binary Search"
         if trigger:
             return reg_binary_search(in_order, element) + middle
         return reg_binary_search(in_order, element)
     else:
-        print "Modified Binary Search"
+        if verbose: print "Modified Binary Search"
         if trigger is False:
             return modified_binary_search(other_slice, element) + middle
         return modified_binary_search(other_slice, element)
@@ -50,5 +50,20 @@ def reg_binary_search(array, element):
         return middle
 
 if __name__=="__main__":
+
     test_list = [4,5,7,9,1,2]
-    print "Expected 4 - got ", modified_binary_search(test_list, 1)
+    result = modified_binary_search(test_list, 1)
+    print "Expected 4 - got ", result
+
+    test_list = [1,2,3,4,5,6,7]
+    result = modified_binary_search(test_list, 1)
+    print "Expected 0 - got ", result
+
+    test_list = [2,3,4,5,6,7,1]
+    result = modified_binary_search(test_list, 1)
+    print "Expected 6 - got ", result
+
+    test_list = [8,1,2,3,4,5,6,7]
+    result = modified_binary_search(test_list, 1)
+    print "Expected 1 - got ", result
+

chapter_9/9.6.py

@@ -2,3 +2,21 @@
 CCC 9.6: Implement an algorithm to print all valid combinations of n-pairs
 of parentheses.
 '''
+
+def paren_func(n):
+    storage = []
+    inner_paren_func("", storage, n, n)
+    return storage
+
+
+def inner_paren_func(base_string, storage, opens_left, closes_left):
+    if opens_left == closes_left == 0:
+        storage.append(base_string)
+    if closes_left > opens_left:
+        inner_paren_func(base_string + ")", storage, opens_left, closes_left-1)
+    if opens_left > 0:
+        inner_paren_func(base_string + "(", storage, opens_left-1, closes_left)
+
+
+if __name__ == "__main__":
+    print paren_func(5)