题目描述

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.

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

Credits:
Special thanks to @mithmatt for adding this problem, creating the above image and all test cases.

分析

题目要求的是两个矩形总的面积，不是相交的面积……

1. 不考虑两个矩形相交，分别求出每个矩形的面积，相加
2. 如果两个矩形不相交，直接返回结果
3. 如果两个矩形相交，减去相交部分面积

代码

    public int computeArea(int A, int B, int C, int D, int E, int F, int G,
            int H) {

        int area = (C - A) * (D - B) + (G - E) * (H - F);

        if (A >= G || B >= H || C <= E || D <= F) {
            return area;
        }

        int top = Math.min(D, H);
        int bottom = Math.max(B, F);
        int left = Math.max(A, E);
        int right = Math.min(C, G);

        return area - (top - bottom) * (right - left);

    }