Java lang.Long.lowestOneBit() method in Java with Examples

java.lang.Long.lowestOneBit() is a built-in method in Java which first convert the number to Binary, then it looks for first set bit present at the lowest position then it reset rest of the bits and then returns the value. In simple language, if the binary expression of a number contains a minimum of a single set bit, it returns 2^(first set bit position from right-1). If the binary expression does not contain any set bit, it returns 0.

Syntax:

public static long lowestOneBit(long num)
Parameters:
num - the number passed 
Returns:
long value by only considering lowest 1 bit in the argument.

Examples:

Input : 36 
Output : 4 
Explanation: Binary Representation = 0010 0100
It considers lowest bit(at 3) and now reset rest of the bits i.e. 0000 0100
so result = 0100 i.e. 4 or in simple terms, the first set 
bit position from right is at position 3, hence 2^2=4  


Input : 1032
Output : 8 

The program below illustrates the java.lang.Long.lowestOneBit() function:

Program 1:

// Java program that demonstrates the use of
// Long.lowestOneBit() function

// include lang package
import java.lang.*;

public class GFG {

    public static void main(String[] args)
    {

        long l = 1032;

        // returns a long value with at most a single one-bit, in the position
        // of the lowest-order ("rightmost") one-bit in the specified int value.
        System.out.println("Lowest one bit = " + Long.lowestOneBit(l));

        l = 45;
        System.out.println("Lowest one bit = " + Long.lowestOneBit(l));
    }
}

Output:

Lowest one bit = 8
Lowest one bit = 1

Program 2: The program below demonstrates the use of function when a negative number is passed.

// java program that demonstrates the use of
// Long.lowestOneBit() function
// negative number

// include lang package
import java.lang.*;

public class GFG {

    public static void main(String[] args)
    {

        long l = -12;

        // prints the binary of a negative expression
        System.out.println("Binary = " + Long.toBinaryString(l));

        // returns a long value with at most a single one-bit, in the position
        // of the lowest-order ("rightmost") one-bit in the specified int value.
        System.out.println("Lowest one bit = " + Long.lowestOneBit(l));
    }
}

Output:

Binary = 1111111111111111111111111111111111111111111111111111111111110100
Lowest one bit = 4

It returns an error message when a decimal a string value is passed as an argument.

Program 3: When a decimal value is passed in argument.

// java program that demonstrates the
// Long.lowestOneBit() function
// decimal value in argument

// include lang package
import java.lang.*;

public class GFG {

    public static void main(String[] args)
    {

        System.out.println("Lowest one bit = " + Long.lowestOneBit(12.34));
    }
}

Output:

prog.java:12: error: incompatible types: possible lossy conversion from double to long
      System.out.println("Lowest one bit = " + Long.lowestOneBit(12.34)); 

Program 4: When a string value is passed in argument.

// java program that demonstrates the
// Long.lowestOneBit() function
// string value in argument

// include lang package
import java.lang.*;

public class GFG {

    public static void main(String[] args)
    {

        System.out.println("Lowest one bit = " + Long.lowestOneBit("12"));
    }
}

Output:

prog.java:12: error: incompatible types: String cannot be converted to long
      System.out.println("Lowest one bit = " + Long.lowestOneBit("12"));