using System;

class Triangle
{
    private int a;
    private int b;
    private int c;

    public Triangle(int a, int b, int c)
    {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    public void Show()
    {
        Console.WriteLine("a: {0}\nb: {1}\nc: {2}", a, b, c);
    }

    public int Perimeter()
    {
        return a + b + c;
    }

    public double Area()
    {
        double p = Perimeter() / 2;
        return Math.Sqrt(p * (p - a) * (p - b) * (p - c));
    }

    public bool Exists()
    {
        if (a <= 0 || b <= 0 || c <= 0) return false;

        double maxSide = Math.Max(Math.Max(a, b), Math.Max(b, c));

        if (maxSide >= a + b + c - maxSide) return false;

        return true;
    }
}