223. Rectangle Area

题目：

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.

链接： http://leetcode.com/problems/rectangle-area/

题解：

数学题，需要判断矩阵是否相交，相交的话减去重复面积(顶点相交除外)。

Time Complexity - O(1)， Space Complexity - O(1)。

public class Solution {
    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 duplicate = (Math.min(C, G) - Math.max(A, E)) * (Math.min(D, H) - Math.max(B, F));
        return area - duplicate;
    }
}

Reference:

https://leetcode.com/discuss/39188/an-easy-to-understand-solution-in-java

https://leetcode.com/discuss/39398/my-java-solution-sum-of-areas-overlapped-area

https://leetcode.com/discuss/43549/just-another-short-way

https://leetcode.com/discuss/43173/if-you-want-to-laugh-look-at-my-solution

https://leetcode.com/discuss/54138/python-concise-solution

https://leetcode.com/discuss/51354/an-explanation-in-plain-language

223. Rectangle Area

原文：http://www.cnblogs.com/yrbbest/p/4993512.html