//This is the edge representation class
import java.text.*;
public class Edge
{
	private int x, y;

	public Edge(int predecessor, int successor){
		this.x = predecessor;
		this.y = successor;
	}
	public int pred() {return x;}
	public int succ() {return y;}

	public String toString() {
				DecimalFormat df = new DecimalFormat("0.##");
       	return "{" + df.format(x) + "," + df.format(y) + "}";


    }
};