1 class Solution {
 2     func minArea(_ image:inout [String],_ x:Int,_ y:Int) -> Int {
 3         var m:Int = image.count
 4         var n:Int = image[0].count
 5         var up:Int = binary_search(&image, true, 0, x, 0, n, true)
 6         var down:Int = binary_search(&image, true, x + 1, m, 0, n, false)
 7         var left:Int = binary_search(&image, false, 0, y, up, down, true)
 8         var right:Int = binary_search(&image, false, y + 1, n, up, down, false)
 9         return (right - left) * (down - up)    
10     }
11     
12     // Binary Search
13     func binary_search(_ image:inout [String],_ h:Bool,_ i:Int,_ j:Int,_ low:Int,_ high:Int,_ opt:Bool) -> Int
14     {
15         var i = i 
16         var j = j
17         while (i < j)
18         {
19             var k:Int = low
20             var mid:Int = (i + j) / 2
21             while (k < high && (h ? image[mid][k] : image[k][mid]) == "0")
22             {
23                 k += 1
24             }
25             if (k < high) == opt{ j = mid }
26             else{ i = mid + 1 }
27         }
28         return i
29     }
30 }
31 
32 //String扩展
33 extension String {        
34     //subscript函数可以检索数组中的值
35     //直接按照索引方式截取指定索引的字符
36     subscript (_ i: Int) -> Character {
37         //读取字符
38         get {return self[index(startIndex, offsetBy: i)]}
39     }
40 }

1 var sol = Solution()
2 var arr:[String] = ["0010","0110","0100"]
3 var x:Int = 0
4 var y:Int = 2
5 print(sol.minArea(&arr,x,y))
6 //Print 6