import java.io.*;
import java.util.*;

public class pi
{
	private static final Scanner cin = new Scanner(System.in);

	public static void main(String[] args)
	{
		while(true) {
			double r = cin.nextDouble();
			if(r == 0.0) { break; }

			double x = 3.0;
			double y = 1.0;

			while(true) {
				x = Math.round(Math.PI * y);

				if(x > Math.PI * y) {
					if(x / y <= Math.PI + r) { break; }
				}
				else {
					if(Math.PI <= x / y + r) { break; }
				}

				y += 1.0;
			}

			System.out.printf("%.0f/%.0f%n", x, y);
		}
	}
}