Moved Tree traversal to a combined py2/py3 implementation

Author: VikingScientist

chapters/tree_traversal/code/python2/Tree_example.py renamed to chapters/tree_traversal/code/python/Tree_example.py

@@ -1,10 +1,12 @@
+from __future__ import print_function
+
+
 class Node:
 
     def __init__(self):
         self.data = None
         self.children = []
 
-
 def create_tree(node, num_row, num_child):
     node.data = num_row
 
@@ -17,7 +19,7 @@ def create_tree(node, num_row, num_child):
 
 def DFS_recursive(node):
     if len(node.children) > 0:
-        print node.data
+        print(node.data)
 
         for child in node.children:
             DFS_recursive(child)
@@ -29,7 +31,7 @@ def DFS_stack(node):
     temp = None
 
     while len(stack) > 0:
-        print stack[-1].data
+        print(stack[-1].data)
         temp = stack.pop()
 
         for child in temp.children:
@@ -42,7 +44,7 @@ def BFS_queue(node):
     temp = None
 
     while len(queue) > 0:
-        print queue[0].data
+        print(queue[0].data)
         temp = queue.pop(0)
 
         for child in temp.children:
@@ -51,13 +53,13 @@ def BFS_queue(node):
 def main():
     tree = create_tree(Node(), 3, 3)
 
-    print "Recursive:"
+    print("Recursive:")
     DFS_recursive(tree)
 
-    print "Stack:"
+    print("Stack:")
     DFS_stack(tree)
 
-    print "Queue:"
+    print("Queue:")
     BFS_queue(tree)
 
 main()

chapters/tree_traversal/code/python3/Tree_example.py

@@ -14,10 +14,8 @@ Trees are naturally recursive data structures, and because of this, we cannot ac
 {% sample lang="js" %}
 This has not been implemented in your chosen language, so here is the Julia code
 [import:3-7, lang:"julia"](code/julia/Tree.jl)
-{% sample lang="py2" %}
-[import:1-5, lang:"python"](code/python2/Tree_example.py)
-{% sample lang="py3" %}
-[import:5-10, lang:"python"](code/python3/Tree_example.py)
+{% sample lang="py" %}
+[import:4-8, lang:"python"](code/python/Tree_example.py)
 {% sample lang="scratch" %}
 This has not been implemented in your chosen language, so here is the Julia code
 [import:3-7, lang:"julia"](code/julia/Tree.jl)
@@ -41,7 +39,7 @@ Because of this, the most straightforward way to traverse the tree might be recu
 {% sample lang="js" %}
 [import:15-23, lang:"javascript"](code/javascript/Tree_example.js)
 {% sample lang="py2" %}
-[import:8-16, lang:"python"](code/python2/Tree_example.py)
+[import:10-18, lang:"python"](code/python/Tree_example.py)
 {% sample lang="py3" %}
 This has not been implemented in your chosen language, so here is the Julia code
 [import:9-16, lang:"julia"](code/julia/Tree.jl)
@@ -156,10 +154,8 @@ In code, it looks like this:
 [import:75-93, lang:"c_cpp"](code/c/tree_traversal.c)
 {% sample lang="js" %}
 [import:25-40, lang:"javascript"](code/javascript/Tree_example.js)
-{% sample lang="py2" %}
-[import:25-36, lang:"python"](code/python2/Tree_example.py)
-{% sample lang="py3" %}
-[import:31-45, lang:"python"](code/python3/Tree_example.py)
+{% sample lang="py" %}
+[import:27-38, lang:"python"](code/python/Tree_example.py)
 {% sample lang="scratch" %}
 This has not been implemented in your chosen language, so here is the Julia code
 [import:45-56, lang:"julia"](code/julia/Tree.jl)
@@ -189,10 +185,8 @@ And this is exactly what Breadth-First Search (BFS) does! On top of that, it can
 [import:95-113, lang:"c_cpp"](code/c/tree_traversal.c)
 {% sample lang="js" %}
 [import:42-57, lang:"javascript"](code/javascript/Tree_example.js)
-{% sample lang="py2" %}
-[import:38-49, lang:"python"](code/python2/Tree_example.py)
-{% sample lang="py3" %}
-[import:48-62, lang:"python"](code/python3/Tree_example.py)
+{% sample lang="py" %}
+[import:40-51, lang:"python"](code/python/Tree_example.py)
 {% sample lang="scratch" %}
 This has not been implemented in your chosen language, so here is the Julia code
 [import:58-69, lang:"julia"](code/julia/Tree.jl)
@@ -225,12 +219,9 @@ tree_traversal.c
 {% sample lang="js" %}
 ### JavaScript
 [import, lang:"javascript"](code/javascript/Tree_example.js)
-{% sample lang="py2" %}
-### Python 2
-[import, lang:"python"](code/python2/Tree_example.py)
-{% sample lang="py3" %}
-### Python 3
-[import, lang:"python"](code/python3/Tree_example.py)
+{% sample lang="py" %}
+### Python 
+[import, lang:"python"](code/python/Tree_example.py)
 {% sample lang="scratch" %}
 ### Scratch
 ![scratch tree](code/scratch/scratch_tree.png)