LeetCode#223 Rectangle Area

Problem Definition:

Find the total area covered by two rectilinear rectangles in a 2D plane.

Each rectangle is defined by its bottom left corner and top right corner as shown in the figure.

Assume that the total area is never beyond the maximum possible value of int.

Solution:

水平方向有三种情况：

1）  A-------------C    

　　　　　　　　　　　　E--------------G

　　或

　　E--------------G

                                  A-------------C

　　条件：E>G||A>G

2）A--------------C

　　　　E-----G

　　或

　　E-------------------G

　　　　A-----------C

　　条件:((C>G) &&(E>A))  ||  ((G>C)&&(A>E))

3）A-------------C

　　　　    E--------------G

　　或

　　E--------------G

　　　　　　A-------------C

　　条件:余下的情况

垂直方向同理。

代码：

def computeArea(self, A, B, C, D, E, F, G, H):
        if E>=C or A>=G or F>=D or B>=H:
            return (C-A)*(D-B)+(G-E)*(H-F)
        if C>G and E>A:
            a=G-E
        elif G>C and A>E:
            a=C-A
        else:
            a=min(G-A,C-E)
        if D>H and F>B:
            b=H-F
        elif H>D and B>F:
            b=D-B
        else:
            b=min(H-B,D-F)
        dup=a*b
        return (C-A)*(D-B)+(G-E)*(H-F)-dup

一种更简便的方法：

def computeArea(self, A, B, C, D, E, F, G, H):
        areaA = (C - A) * (D - B)
        areaB = (G - E) * (H - F)
        l = max(0, min(C, G) - max(A, E))
        h = max(0, min(D, H) - max(B, F))
        return areaA + areaB - l * h