power of three

Author: jackzhenguo

Math/Math.Lib/PowerOfThreeSln.cs

@@ -0,0 +1,29 @@
+/* ==============================================================================
+ * 功能描述：UglyNumberSln  
+ * 创 建 者：gz
+ * 创建日期：2017/5/26 12:23:33
+ * ==============================================================================*/
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+// Given an integer, write a function to determine if it is a power of three.
+// Follow up: 
+// Could you do it without using any loop / recursion?
+namespace Math.Lib
+{
+    /// <summary>
+    /// PowerOfThreeSln
+    /// </summary>
+    public class PowerOfThreeSln
+    {
+		public boolean isPowerOfThree(int n) 
+		{
+			int powcnt = 0;
+			if(Math.Pow(3,19)<Int32.MaxValue && Math.Pow(3,20)>Int32.MaxValue)
+			   powcnt = 19;
+			return ( n>0 &&  Math.Pow(3,19)%n==0);
+		}
+
+    }
+}