| #!/usr/bin/python |
| """ turtle-example-suite: |
| |
| tdemo_minimal_hanoi.py |
| |
| A minimal 'Towers of Hanoi' animation: |
| A tower of 6 discs is transferred from the |
| left to the right peg. |
| |
| An imho quite elegant and concise |
| implementation using a tower class, which |
| is derived from the built-in type list. |
| |
| Discs are turtles with shape "square", but |
| stretched to rectangles by shapesize() |
| --------------------------------------- |
| To exit press STOP button |
| --------------------------------------- |
| """ |
| from tkinter.turtle import * |
| |
| class Disc(Turtle): |
| def __init__(self, n): |
| Turtle.__init__(self, shape="square", visible=False) |
| self.pu() |
| self.shapesize(1.5, n*1.5, 2) # square-->rectangle |
| self.fillcolor(n/6., 0, 1-n/6.) |
| self.st() |
| |
| class Tower(list): |
| "Hanoi tower, a subclass of built-in type list" |
| def __init__(self, x): |
| "create an empty tower. x is x-position of peg" |
| self.x = x |
| def push(self, d): |
| d.setx(self.x) |
| d.sety(-150+34*len(self)) |
| self.append(d) |
| def pop(self): |
| d = list.pop(self) |
| d.sety(150) |
| return d |
| |
| def hanoi(n, from_, with_, to_): |
| if n > 0: |
| hanoi(n-1, from_, to_, with_) |
| to_.push(from_.pop()) |
| hanoi(n-1, with_, from_, to_) |
| |
| def play(): |
| onkey(None,"space") |
| clear() |
| hanoi(6, t1, t2, t3) |
| write("press STOP button to exit", |
| align="center", font=("Courier", 16, "bold")) |
| |
| def main(): |
| global t1, t2, t3 |
| ht(); penup(); goto(0, -225) # writer turtle |
| t1 = Tower(-250) |
| t2 = Tower(0) |
| t3 = Tower(250) |
| # make tower of 6 discs |
| for i in range(6,0,-1): |
| t1.push(Disc(i)) |
| # prepare spartanic user interface ;-) |
| write("press spacebar to start game", |
| align="center", font=("Courier", 16, "bold")) |
| onkey(play, "space") |
| listen() |
| return "EVENTLOOP" |
| |
| if __name__=="__main__": |
| msg = main() |
| print(msg) |
| mainloop() |