[LeetCode]223. 矩形面积

矩形面积

Posted by JinFei on September 30, 2021

题目描述

给你 二维 平面上两个 由直线构成的 矩形,请你计算并返回两个矩形覆盖的总面积。 每个矩形由其 左下 顶点和 右上 顶点坐标表示: 第一个矩形由其左下顶点 (ax1, ay1) 和右上顶点 (ax2, ay2) 定义。 第二个矩形由其左下顶点 (bx1, by1) 和右上顶点 (bx2, by2) 定义。

Example1:

images 输入:ax1 = -3, ay1 = 0, ax2 = 3, ay2 = 4, bx1 = 0, by1 = -1, bx2 = 9, by2 = 2 输出:45

Example2:

输入:ax1 = -2, ay1 = -2, ax2 = 2, ay2 = 2, bx1 = -2, by1 = -2, bx2 = 2, by2 = 2 输出:16

Note:

  • -10^4 <= ax1, ay1, ax2, ay2, bx1, by1, bx2, by2 <= 10^4

解题思路

  • 需要找到矩形重叠的坐标
  • 注意无重叠的情况
class Solution {
public:
    int computeArea(int ax1, int ay1, int ax2, int ay2, int bx1, int by1, int bx2, int by2) {
        int area1 = (ax2 - ax1) * (ay2 - ay1);
        int area2 = (bx2 - bx1) * (by2 - by1);
        int overlapWidth = min(ax2, bx2) - max(bx1, ax1);
        int overlapHeight = min(ay2, by2) - max(ay1, by1);
        int overlapArea = max(overlapWidth, 0) * max(overlapHeight, 0);
        return area1 + area2 - overlapArea;
    }
};