JavaAlgorithms/Maths/PerfectSquare.java

package Maths;

/** https://en.wikipedia.org/wiki/Perfect_square */
public class PerfectSquare {
  public static void main(String[] args) {
    assert !isPerfectSquare(-1);
    assert !isPerfectSquare(3);
    assert !isPerfectSquare(5);
    assert isPerfectSquare(9);
    assert isPerfectSquare(100);
  }

  /**
   * Check if a number is perfect square number
   *
   * @param number the number to be checked
   * @return <tt>true</tt> if {@code number} is perfect square, otherwise <tt>false</tt>
   */
  public static boolean isPerfectSquare(int number) {
    int sqrt = (int) Math.sqrt(number);
    return sqrt * sqrt == number;
  }
}