save project

my_tree.py

@@ -6,7 +6,7 @@ pen.color('sienna')
 w = turtle.Screen()
 w = turtle.Screen()
 w.bgcolor('wheat')
 w.bgcolor('wheat')
 pen.down()      # wheat小麦
 pen.down()      # wheat小麦
-
+pen.seth(90)
 # 移动到起点
 # 移动到起点
 def tree(n):
 def tree(n):
     if n >= 50:
     if n >= 50:
@@ -17,7 +17,7 @@ def tree(n):
         tree(n-50)
         tree(n-50)
         pen.right(30)
         pen.right(30)
         pen.up()
         pen.up()
-        pen.backward(50)    # 后退
+        pen.backward(n)    # 后退
         pen.down()
         pen.down()
 
 
 tree(100)        
 tree(100)