save project

my_tree.py

@@ -7,17 +7,23 @@ w = turtle.Screen()
 w.bgcolor('wheat')      # wheat小麦
 
 # 移动到起点
+def tree(n):
+    if n>=0:
+        pen.forward(n)
+        pen.right(30)
+        tree(n-10)
+        pen.left(60)
+        tree(n-10)
+        pen.right(30)
+        pen.up()
+        pen.backward(n)    # 后退
+        pen.down()
+
+
 pen.left(90)
 pen.up()
-pen.backward(150)    # 后退
+pen.backward(150)
 pen.down()
-pen.forward(100)
-pen.right(30)
-pen.forward(50)
-pen.backward(50)
-pen.left(60)
-pen.forward(50)
-pen.backward(50)
-pen.up()
 
+tree(60)
 turtle.done()