save project

my_tree.py

@@ -13,22 +13,23 @@ pen.backward(150)    # 后退
 pen.down()
 
 def tree(n):
-    if n >= 50:
-        pen.forward(n)
-        pen.right(30)
-        pen.forward(n-10)
-        tree(n-10)
-        pen.up()
-        pen.backward(n-10)
-        pen.left(60)
-        pen.down()
-        pen.forward(n-10)
-        pen.up()
-        pen.backward(n)
-        pen.down()
-        pen.right(30)
-        pen.up()
-        pen.backward(100)
+    if n < 50:
+        return
+    pen.forward(n)
+    pen.right(30)
+    tree(n-10)
+    pen.forward(n-10)
+    pen.up()
+    pen.backward(n-10)
+    pen.left(60)
+    pen.down()
+    tree(n-10)
+    pen.forward(n-10)
+    pen.up()
+    pen.backward(n-10)
+    pen.right(30)
+    pen.up()
+    pen.backward(n)
 tree(100)
 pen.down()
 turtle.done()