Python输入输出练习，运算练习，turtle初步练习

print("Hello World")

name = input("输入姓名")
print("{}同学，好好学习，天天向上".format(name))

a=input("请输入a:")
b=input("请输入b:")
print(float(a)+float(b))

a=input("a=")
b=input("b=")
c=input("c=")
l=(float(a)+float(b)+float(c))/2
d=float(l)*(float(l)-float(a))*(float(l)-float(b))*(float(l)-float(c))
s=float(d)**0.5
print(float(s))

r=input("请输入r=")
s=3.14*float(r)*float(r)
print(float(s))

import turtle

turtle.circle(10)
turtle.circle(20)
turtle.circle(30)
turtle.circle(100)

import turtle

for i in range(5):
  turtle.forward(100)
  turtle.right(144)

import turtle

turtle.fillcolor("yellow")
turtle.begin_fill()
for i in range(5):
    turtle.forward(100)
    turtle.right(144)

turtle.end_fill()