10242 - Fourth Point !!

題目敘述：here

解題想法：

• 題目給定平行四邊形的「兩個相鄰邊」的端點的 (x, y)座標，這四個端點中必有兩個座標是同一點。


• 決定三個相異的座標點後，即可決定第四點的座標。

流程圖：

程式碼：

          
#  鄒雨笙 UVa Online Judge 2023/10/21

#  Problem 10242 - Fourth Point !!


while True:
    try:
        points = input().split()
        
        if len(points) != 8:
            continue

        points = [float(x) for x in points]

        x1, y1, x2, y2, x3, y3, x4, y4 = points

        if x1 == x3 and y1 == y3:
            x1, y1, x2, y2, x3, y3 = x2, y2, x3, y3, x4, y4
        elif x1 == x4 and y1 == y4:
            x1, y1, x2, y2 = x2, y2, x4, y4
        elif x2 == x3 and y2 == y3:
            x2, y2, x3, y3 = x3, y3, x4, y4
        elif x2 == x4 and y2 == y4:
            x2, y2 = x4, y4

        vector = (x1 - x2, y1 - y2)
        point4 = (x3 + vector[0], y3 + vector[1])

        print(f"{point4[0]:.3f} {point4[1]:.3f}")

    except EOFError:
        break
    except ValueError:
        continue