Solution Spiral matrix

Author: doitduri

spiral-matrix/doitduri.swift

@@ -0,0 +1,42 @@
+class Solution {
+    func spiralOrder(_ matrix: [[Int]]) -> [Int] {
+        guard !matrix.isEmpty else { return [] }
+        
+        var answer: [Int] = []
+        
+        var top = 0
+        var bottom = matrix.count - 1
+        var left = 0
+        var right = matrix[0].count - 1
+        
+        while top <= bottom && left <= right {
+            for i in left...right {
+                answer.append(matrix[top][i])
+            }
+            top += 1
+            
+            if top <= bottom {
+                for i in top...bottom {
+                    answer.append(matrix[i][right])
+                }
+            }
+            right -= 1
+            
+            if top <= bottom && left <= right {
+                for i in stride(from: right, through: left, by: -1) {
+                    answer.append(matrix[bottom][i])
+                }
+                bottom -= 1
+            }
+            
+            if left <= right && top <= bottom {
+                for i in stride(from: bottom, through: top, by: -1) {
+                    answer.append(matrix[i][left])
+                }
+                left += 1
+            }
+        }
+        
+        return answer
+    }
+}