Given a set of points in the xy-plane, determine the minimum area of any rectangle formed from these points, with sides not necessarily parallel to the x and y axes.
If there isn‘t any rectangle, return 0.
Example 1:
Input: [[1,2],[2,1],[1,0],[0,1]] Output: 2.00000 Explanation: The minimum area rectangle occurs at [1,2],[2,1],[1,0],[0,1], with an area of 2.
Example 2:
Input: [[0,1],[2,1],[1,1],[1,0],[2,0]] Output: 1.00000 Explanation: The minimum area rectangle occurs at [1,0],[1,1],[2,1],[2,0], with an area of 1.
Example 3:
Input: [[0,3],[1,2],[3,1],[1,3],[2,1]] Output: 0 Explanation: There is no possible rectangle to form from these points.
Example 4:
Input: [[3,1],[1,1],[0,1],[2,1],[3,3],[3,2],[0,2],[2,3]] Output: 2.00000 Explanation: The minimum area rectangle occurs at [2,1],[2,3],[3,3],[3,1], with an area of 2.
Note:
1 <= points.length <= 50
0 <= points[i][0] <= 40000
0 <= points[i][1] <= 40000
- All points are distinct.
- Answers within
10^-5
of the actual value will be accepted as correct.
给定在 xy 平面上的一组点,确定由这些点组成的任何矩形的最小面积,其中矩形的边不一定平行于 x 轴和 y 轴。
如果没有任何矩形,就返回 0。
示例 1:
输入:[[1,2],[2,1],[1,0],[0,1]] 输出:2.00000 解释:最小面积的矩形出现在 [1,2],[2,1],[1,0],[0,1] 处,面积为 2。
示例 2:
输入:[[0,1],[2,1],[1,1],[1,0],[2,0]] 输出:1.00000 解释:最小面积的矩形出现在 [1,0],[1,1],[2,1],[2,0] 处,面积为 1。
示例 3:
输入:[[0,3],[1,2],[3,1],[1,3],[2,1]] 输出:0 解释:没法从这些点中组成任何矩形。
示例 4:
输入:[[3,1],[1,1],[0,1],[2,1],[3,3],[3,2],[0,2],[2,3]] 输出:2.00000 解释:最小面积的矩形出现在 [2,1],[2,3],[3,3],[3,1] 处,面积为 2。
提示:
1 <= points.length <= 50
0 <= points[i][0] <= 40000
0 <= points[i][1] <= 40000
- 所有的点都是不同的。
- 与真实值误差不超过
10^-5
的答案将视为正确结果。
460ms
1 class Solution { 2 func minAreaFreeRect(_ points: [[Int]]) -> Double { 3 var ans:Double = -1 4 var set:Set<Int> = Set<Int>() 5 for p in points 6 { 7 set.insert((p[0] << 16) | p[1]) 8 } 9 10 var n:Int = points.count 11 for i in 0..<n 12 { 13 for j in 0..<n 14 { 15 var x0:Int = points[j][0] - points[i][0] 16 var y0:Int = points[j][1] - points[i][1] 17 if i != j 18 { 19 for k in 0..<n 20 { 21 if i != k && j != k 22 { 23 var x1:Int = points[k][0] - points[i][0] 24 var y1:Int = points[k][1] - points[i][1] 25 if x0 * x1 + y0 * y1 == 0 26 { 27 var x:Int = points[j][0] + points[k][0] - points[i][0] 28 var y:Int = points[j][1] + points[k][1] - points[i][1] 29 if set.contains((x << 16) | y) 30 { 31 var cur:Double = sqrt(Double(x0 * x0 + y0 * y0)) * sqrt(Double(x1 * x1 + y1 * y1)) 32 if ans < 0 || ans > cur 33 { 34 ans = cur 35 } 36 } 37 } 38 } 39 } 40 } 41 } 42 } 43 return ans < 0 ? 0 : ans 44 } 45 }
原文地址:https://www.cnblogs.com/strengthen/p/10165340.html
时间: 2024-10-08 16:06:01