# -*- coding: gbk -*-
# Written By Vincent
import turtle

num = eval(input("边数:"))
lenth = float(input("边长:"))
color = input("填充颜色:")
flag = input("你确定要画吗?Y/N\n")
if flag == 'Y': 
	turtle.screensize(800,600, "white")
	turtle.fillcolor(color)
	angle = 180 - (num -2) * 180 / num
	turtle.begin_fill()
	turtle.penup()
	turtle.goto(-100,200)
	turtle.pendown()
	for i in range(num):
		turtle.forward(lenth)
		turtle.right(angle)
	turtle.end_fill()
	turtle.done()
else:
	print("再见,朋友。")