836_Rectangle_Overlap

Author: qiyuangong

README.md

@@ -184,6 +184,7 @@ Also, there are open source implementations for basic data structs and algorithm
 | 811 | [Subdomain Visit Count](https://leetcode.com/problems/subdomain-visit-count/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/811_Subdomain_Visit_Count.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/811_Subdomain_Visit_Count.java) | String split and HashMap, O(n) and O(n) |
 | 819 | [Most Common Word](https://leetcode.com/problems/most-common-word/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/819_Most_Common_Word.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/819_Most_Common_Word.java) | String processing, be careful about 'b,b,b'. regex is recommended. |
 | 832 | [Flipping an Image](https://leetcode.com/problems/flipping-an-image/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/832_Flipping_an_Image.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/832_Flipping_an_Image.java) | Invert and swap can be done at the same time, and careful about (n + 1)/2, O(n^2) and O(1) |
+| 836 | [Rectangle Overlap](https://leetcode.com/problems/rectangle-overlap/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/836_Rectangle_Overlap.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/836_Rectangle_Overlap.java) | 1. Check position, O(1) and O(1)<br>2. Check area, O(1) and O(1)  |
 | 844 | [Backspace String Compare](https://leetcode.com/problems/backspace-string-compare/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/844_Backspace_String_Compare.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/844_Backspace_String_Compare.java) | 1. Stack pop when encounters #, O(n) and O(n)<br>2. Compare string from end to start, O(n) and O(1) |
 | 852 | [Peak Index in a Mountain Array](https://leetcode.com/problems/peak-index-in-a-mountain-array/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/852_Peak_Index_in_a_Mountain_Array.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/852_Peak_Index_in_a_Mountain_Array.java) | 1. Scan the array until encountering decline, O(n) and O(1)<br>2. Binary seach with additional check for [i + 1], O(logn) and O(1) |
 | 867 | [Transpose Matrix](https://leetcode.com/problems/transpose-matrix/) | [Python](https://github.com/qiyuangong/leetcode/blob/master/python/867_Transpose_Matrix.py) [Java](https://github.com/qiyuangong/leetcode/blob/master/java/867_Transpose_Matrix.java) | Res[i][j] = A[j][i] |

java/836_Rectangle_Overlap.java

@@ -0,0 +1,22 @@
+class Solution {
+    /*public boolean isRectangleOverlap(int[] rec1, int[] rec2) {
+        // Check position
+        return !(rec1[2] <= rec2[0] ||   // left
+                 rec1[3] <= rec2[1] ||   // bottom
+                 rec1[0] >= rec2[2] ||   // right
+                 rec1[1] >= rec2[3]);    // top
+    }*/
+    /*public boolean isRectangleOverlap(int[] rec1, int[] rec2) {
+        // Check area
+        // https://leetcode.com/problems/rectangle-area/discuss/62149/Just-another-short-way
+        int left = Math.max(rec1[0], rec2[0]), right = Math.max(Math.min(rec1[2], rec2[2]), left);
+        int bottom = Math.max(rec1[1], rec2[1]), top = Math.max(Math.min(rec1[3], rec2[3]), bottom);
+        return (right - left) * (top - bottom) != 0;
+    }*/
+
+    public boolean isRectangleOverlap(int[] rec1, int[] rec2) {
+        // Check area
+        return (Math.min(rec1[2], rec2[2]) > Math.max(rec1[0], rec2[0]) && // width > 0
+                Math.min(rec1[3], rec2[3]) > Math.max(rec1[1], rec2[1]));  // height > 0
+    }
+}

python/836_Rectangle_Overlap.py

@@ -0,0 +1,17 @@
+class Solution(object):
+    def isRectangleOverlap(self, rec1, rec2):
+        """
+        :type rec1: List[int]
+        :type rec2: List[int]
+        :rtype: bool
+        """
+        return not (rec1[2] <= rec2[0] or  # left
+                    rec1[3] <= rec2[1] or  # bottom
+                    rec1[0] >= rec2[2] or  # right
+                    rec1[1] >= rec2[3])    # top
+
+    # def isRectangleOverlap(self, rec1, rec2):
+    #     def intersect(p_left, p_right, q_left, q_right):
+    #         return min(p_right, q_right) > max(p_left, q_left)
+    #     return (intersect(rec1[0], rec1[2], rec2[0], rec2[2]) and
+    #             intersect(rec1[1], rec1[3], rec2[1], rec2[3]))