Tilde Operator in Java

The bitwise complement operator falls under the category of the unary operator (deals with just a single operand). It takes one number and reverses all pieces of it. When a bitwise administrator is applied on bits, then, at that point, all the 1's turned into 0's and the other way around. The operator for the bitwise complement is ~ (Tilde).

Example:

Input: ~ 0000 0011

Output: 1111 1100

Input: 1110 0111

Output: 0001 1000

The bitwise complement operator ought to be utilized cautiously. The consequence of the ~ tilde operator on a modest number can be a major number on the off chance that the outcome is put away in an unsigned variable. Furthermore, the outcome might be a negative number on the off chance that the outcome is put away in a marked variable (expecting that the negative numbers are put away in 2's complement structure where the furthest left bit is the signed bit).

Input:

n = 2

Binary form of 2 = 0010

Tilde operator on 2 = ~ 0010 = 1101

The decimal value of 1101 is 13.

Expected output: 13

Correct Output: -3

The 2's complement is returned by the compiler.

Example1: program for working of tilde operator

// Java program to demonstrate the working of the Tilde operator in Java (Bitwise Complement Operator)

// importing the required packages
import java.io.*;
import java.util.*;

class Example1 {
    public static void main(String[] args)
    {
        System.out.println("Hello, World!");
        // Creating an object to the Scanner class such that we can take the inputs from the user
        Scanner sc = new Scanner(System.in);
        System.out.println(" Enter a number: ");
        // reading a number from user
        int a = sc.nextInt();
        // storing the Bitwise Complement in b
        int b = ~a;
        // printing the value of b
        System.out.println(" The Tilde operator (Bitwise Complement Operator) on " + a + " is: " + b );
        
    }
}

Output:

Explanation: The tilde of 2 (~2) is - 3 rather than 13. However, why?

At the point when numbers are imprinted in base-10, the consequence of a NOT activity can shock. Specifically, positive numbers can become negative and the other way around.

How about we first track down the twofold portrayal of the bitwise complement of 2, which is - 3

The negative numbers are sorted as the two's complement of the positive partner.

2's complement:

The 2's complement is applicable to binary numbers. The 2's complement of a number is equivalent to the supplement of that number in addition to 1.

Example:

Tilde Operation of 2 (~ 0010) is: 1101

Now calculate the 2's complement of 3:

The Binary form of 3 is = 0011

Now add 1 to the 1's complement of 3 = 1100

Adding 1 to 1's complement = 1100 +1

2's complement of 3 = 1101

Note:

The bitwise Complement of 2 is same as the binary representation of -3

For any number n, the bitwise complement of n will be - (n+1).
Bitwise complement of N = ~N (addressed in 2's supplement structure).
2'complement of ~N= - (~(~N)+1) = - (N+1).

Example-2: program to find 2's complement

Main.java

// Java program to find 2's complement

// importing the required packages
import java.util.*;
public class Main
{
	static String find(StringBuffer str)
	{
		int n = str.length();
		int i;
		for (i = n-1 ; i >= 0 ; i--)
			if (str.charAt(i) == '1')
				break;
		if (i == -1)
			return "1" + str;
		for (int k = i-1 ; k >= 0; k--)
		{
			//Just flip the values
			if (str.charAt(k) == '1')
				str.replace(k, k+1, "0");
			else
				str.replace(k, k+1, "1");
		}
		// returns the 2's complement
		return str.toString();
	}
	
	// Driver method
	public static void main(String[] args)
	{
	    // creating an object to the scanner class such that to read the input from the user
		Scanner sc = new Scanner(System.in);
		System.out.println(" Enter a binary String = ");
		// reading binary string
		String s = sc.next();
		// Creating an object to the StingBuffer to create a StringBuffer
		StringBuffer str = new StringBuffer(s);
		// printing the 2's complement
		System.out.println(" The 2's complement of " + s + " is = " + find(str));
	}
}

Output: