How To Role Bitwise Operator Inwards Java? Ability Of 2 Example

In this Java Programming tutorial y'all volition larn how to cheque if number is Power of ii using bitwise operator. Main role or this programme is to learn y'all how to work bit-wise operators similar  bitwise AND (&)  in Java. Influenza A virus subtype H5N1 number is said to endure ability of ii if all its prime number factors are 2, but inwards binary Blue Planet things industrial plant footling differently. If y'all stimulate got read hacker's delight majority together with then y'all know that at that spot are several technique to cheque if a number is ability of ii or not, i of them is performing bit-wise AND functioning betwixt number together with number -1, if number is zilch together with then number is ability of two. Just remember, hither nosotros are doing binary subtraction together with non decimal one. In bitwise operator, each fleck is used inwards evaluation for instance if y'all work bitwise AND together with then each fleck of both operand volition become through AND functioning together with number volition comprise 1 solely if both bits are i otherwise zero. I volition explicate how precisely this programme work, but let's commencement regard the programme itself.

Java Program to Check if Number is Power of Two

Here is my solution of this problem. Of-course at that spot are many ways to solve this problem, including yesteryear using arithmetics operator equally shown inwards my earlier post, but I stimulate got purposefully used bit-wise operator to exhibit how slowly together with fast is to devise an algorithm using bit-wise operators. This programme is a real proficient instance of learning bit-wise operator inwards Java.

/**  * Java Program to cheque if a number is ability of ii or not.  *  * @author Javin  */ public class PowerOfTwo{      public static void main(String args[]) {         System.out.printf("is %d ability of Two? %b%n", 2, isPowerofTwo(2));         System.out.printf("is %d ability of Two? %b%n", 4, isPowerofTwo(4));         System.out.printf("is %d ability of Two? %b%n", 5, isPowerofTwo(5));         System.out.printf("is %d ability of Two? %b%n", 1, isPowerofTwo(1));         System.out.printf("is %d ability of Two? %b%n", -1, isPowerofTwo(-1));     }      /*      * @return true, if number is ability of two, otherwise false.      */     public static boolean isPowerofTwo(int number) {         return (number & (number - 1)) == 0;     }  }  Output is 2 ability of Two? true is 4 ability of Two? true is 5 ability of Two? false is 1 ability of Two? true is -1 ability of Two? false

Explanation :
Though this solution is just a beautiful i liner, it may accept to a greater extent than or less fourth dimension for y'all to sympathise what's happening. To become far simple, let's start amongst the code itself number & (number - 1)) == 0, So what are nosotros doing here? Basically wee are checking if number & (number - 1) is equal to zilch together with then number is ability of two. We are doing ii functioning inwards this code, commencement is binary subtraction together with instant is bitwise AND operation. Let's commencement regard how bitwise AND operator works. As advert advise it performs AND functioning on every unmarried fleck of both operand, bit-wise AND volition furnish 0 solely if both operand don't stimulate got a gear upwards fleck (1) at same location. In other words, if commencement operand has 0 at LSB together with then instant operand must stimulate got 1 or vice-versa, but they must non stimulate got 1 at same position. Now let's come upwards dorsum to binary subtraction,  If y'all produce binary subtraction yesteryear hand, y'all volition realize that it at-least alter your LSB from 0 to 1, together with tin flame switch the fleck until it run across a 1 equally shown below

  1000
- 0001
-------
  0111

So inwards social club for a number to endure a ability of ii it must follow a designing where if number = abcd1000 together with then n-1 = abcd0111 together with abcd must endure zero.

Since whatever binary number, which is ability of ii has precisely i gear upwards bit, together with subtracting i from that volition brand all lower bits 1, (number & (number-1) will ever endure zilch for number which is ability of two.

That's all close how to detect if a number is ability of ii inwards Java. As I said, at that spot are multiple ways to solve this problem, y'all tin flame either work arithmetics operator e.g. partitioning or modulo operator or y'all tin flame only work bit-wise operator, just similar I stimulate got used here.  If y'all are equally good serious close improving your noesis on bitwise operator, together with then y'all should read hacker's delight, a bully majority for programmers.

Further Learning
The Coding Interview Bootcamp: Algorithms + Data Structures
Data Structures together with Algorithms: Deep Dive Using Java
Algorithms together with Data Structures - Part 1 together with 2

If y'all similar this coding job together with desire to do to a greater extent than to amend your coding skill, together with then y'all tin flame equally good search for Java programming exercises inwards this blog.