public class PiApprox {

	public static String iterPi2String(Double epsilon) {
		 // your code
     System.out.println(epsilon);
     System.out.printf("%f\n", epsilon);
     long STOP = (long)(1.0d / epsilon);
     System.out.println(STOP);
     double sum = 1;
     int den = 3;
     for(long i = 1; i < STOP; i++){
       if(i % 2 == 1){
         sum -= (1.0 / (double)den);
       }
       else{
         sum += (1.0 / (double)den);
       }
       den += 2;
     }
     String toReturn = "[" + STOP + ", ";
     toReturn += String.format("%.10f", sum * 4);
     toReturn += "]";
     return toReturn;
	}
}