using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Enter the ךength of the sides:");

        int side1 = int.Parse(Console.ReadLine());

        int side2 = int.Parse(Console.ReadLine());

        int side3 = int.Parse(Console.ReadLine());

        if (side1<side2+side3 && side2<side1+side3 && side3<side2+side1)

            Console.WriteLine("Possible triangle");

        else

            Console.WriteLine("Impossible triangle");

    }

}