JavaAlgorithms/Maths/PowerOfTwoOrNot.java

package Maths;

/** A utility to check if a given number is power of two or not. For example 8,16 etc. */
public class PowerOfTwoOrNot {

  public static void main(String[] args) {
    assert !checkIfPowerOfTwoOrNot(0);
    assert checkIfPowerOfTwoOrNot(1);
    assert checkIfPowerOfTwoOrNot(8);
    assert checkIfPowerOfTwoOrNot(16);
    assert checkIfPowerOfTwoOrNot(1024);
  }

  /**
   * Checks whether given number is power of two or not.
   *
   * @param number the number to check
   * @return {@code true} if given number is power of two, otherwise {@code false}
   */
  public static boolean checkIfPowerOfTwoOrNot(int number) {
    return number != 0 && ((number & (number - 1)) == 0);
  }
}