name=input("What's your name:")
print("{},it is good for you to study Phython!".format(name))
a=input("a:")
b=input("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("r=")
s=3.14*float(r)*float(r)
print(float(s))
import turtle
turtle.shape('turtle')
turtle.speed(5)
turtle.color('red')
turtle.circle(50)
turtle.circle(75)
turtle.circle(100)
import turtle
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
import turtle
turtle.shape('turtle')
turtle.speed(50)
turtle.color('green')
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)
turtle.forward(200)
turtle.right(144)