Day i do not know

542. 01 Matrix/Program.cs

@@ -0,0 +1,15 @@
+namespace _542._01_Matrix;
+
+internal class Program
+{
+    static void Main(string[] args)
+    {
+        int[][] mat = new int[][] { new int[] { 0,0,0, },
+                                    new int[] { 0,1,0, },
+                                    new int[] { 1,1,1, },
+        };
+        var res = new Solution().UpdateMatrix(mat);
+        foreach(var row in res)
+            Console.WriteLine(String.Join(" ", row));
+    }
+}