# 这个是4.31的代码，一个函数里包含了。在线上，在线左，在线右
def judgePoint(x0, y0, x1, y1, x2, y2):
    juMethod = ((x1 - x0) * (y2 - y0)) - ((x2 - x0) * (y1 - y0))
    if juMethod > 0:
        print("p2 is on the left side of the line from p0 to p1")
    elif juMethod == 0:
        print("p2 is on the same line from p0 to p1")
    elif juMethod < 0:
        print("p2 is on the right side of the line from p0 to p1")
    turtle.penup()
    turtle.goto(x0, y0)
    turtle.dot(6, 'red')
    turtle.pendown()
    turtle.goto(x1, y1)
    turtle.dot(6, 'red')
    turtle.penup()
    turtle.goto(x2, y2)
    turtle.dot(6, 'blue')
    turtle.hideturtle()
    turtle.done()


judgePoint(34, 20, 65, 95, -50, 40)
judgePoint(10, 10, 50, 50, 20, 20)
judgePoint(34, 20, 65, 95, 50, 25)

def leftOfTheLine(x0, y0, x1, y1, x2, y2):
    juMethod = ((x1 - x0) * (y2 - y0)) - ((x2 - x0) * (y1 - y0))
    if juMethod > 0:
        print("p2 is on the left side of the line from p0 to p1")

    turtle.penup()
    turtle.goto(x0, y0)
    turtle.dot(6, 'red')
    turtle.pendown()
    turtle.goto(x1, y1)
    turtle.dot(6, 'red')
    turtle.penup()
    turtle.goto(x2, y2)
    turtle.dot(6, 'blue')
    turtle.hideturtle()
    turtle.done()


def onTheSameLine(x0, y0, x1, y1, x2, y2):
    juMethod = ((x1 - x0) * (y2 - y0)) - ((x2 - x0) * (y1 - y0))

    if juMethod == 0:
        print("p2 is on the same line from p0 to p1")

    turtle.penup()
    turtle.goto(x0, y0)
    turtle.dot(6, 'red')
    turtle.pendown()
    turtle.goto(x1, y1)
    turtle.dot(6, 'red')
    turtle.penup()
    turtle.goto(x2, y2)
    turtle.dot(6, 'blue')
    turtle.hideturtle()
    turtle.done()


def onTheLineSegment(x0, y0, x1, y1, x2, y2):
    juMethod = ((x1 - x0) * (y2 - y0)) - ((x2 - x0) * (y1 - y0))

    if juMethod < 0:
        print("p2 is on the right side of the line from p0 to p1")
    turtle.penup()
    turtle.goto(x0, y0)
    turtle.dot(6, 'red')
    turtle.pendown()
    turtle.goto(x1, y1)
    turtle.dot(6, 'red')
    turtle.penup()
    turtle.goto(x2, y2)
    turtle.dot(6, 'blue')
    turtle.hideturtle()
    turtle.done()

# 此三段代码一次运行一个，不能同时哦
leftOfTheLine(34, 20, 65, 95, -50, 40)
onTheSameLine(10, 10, 50, 50, 20, 20)
onTheLineSegment(34, 20, 65, 95, 50, 25)