code: import java.util.Locale;
  
  public class Test {
  
      public static void main(String[] a) {
          for (int n = 2; n < 6; n++)
              unity(n);
      }
  
      public static void unity(int n) {
          System.out.printf("%n%d: ", n);
  
          //all the way around the circle at even intervals
          for (double angle = 0; angle < 2 * Math.PI; angle += (2 * Math.PI) / n) {
  
              double real = Math.cos(angle); //real axis is the x axis
  
              if (Math.abs(real) < 1.0E-3)
                  real = 0.0; //get rid of annoying sci notation
  
              double imag = Math.sin(angle); //imaginary axis is the y axis
  
              if (Math.abs(imag) < 1.0E-3)
                  imag = 0.0;
  
              System.out.printf(Locale.US, "(%9f,%9f) ", real, imag);
          }
      }
  }
  