Power of Four

Author: parshva45

Diff for: Power of Four.js

@@ -0,0 +1,17 @@
+/*Given an integer (signed 32 bits), write a function to check whether it is a power of 4.
+
+Example:
+Given num = 16, return true. Given num = 5, return false.
+
+Follow up: Could you solve it without loops/recursion?*/
+
+/**
+ * @param {number} num
+ * @return {boolean}
+ */
+var isPowerOfFour = function(num) {
+    if(num <= 0)
+        return false
+    var power = Math.round(Math.log(num)/Math.log(4))
+    return Math.pow(4,power) == num
+};