836. Rectangle Overlap

A rectangle is represented as a list [x1, y1, x2, y2], where (x1, y1) are the coordinates of its bottom-left corner, and (x2, y2) are the coordinates of its top-right corner.

Two rectangles overlap if the area of their intersection is positive.  To be clear, two rectangles that only touch at the corner or edges do not overlap.

Given two (axis-aligned) rectangles, return whether they overlap.

Example 1:

Input: rec1 = [0,0,2,2], rec2 = [1,1,3,3]
Output: true



Example 2:

Input: rec1 = [0,0,1,1], rec2 = [1,0,2,1]
Output: false

判断两个矩阵是否重叠。

不重叠的情况：矩阵1的上边不高于矩阵2的下边，或者矩阵1的右边不宽于矩阵2的左边。

class Solution {
public:
    bool isRectangleOverlap(vector<int>& rec1, vector<int>& rec2) {
        if (rec2[0] >= rec1[2] || rec2[1] >= rec1[3])
            return false;
        if (rec1[0] >= rec2[2] || rec1[1] >= rec2[3])
            return false;
        return true;
    }
};