using System;

interface IPt {
    float X { get; }
    float Y { get; }
}

class Pt: IPt {
    public float X { get; set; }
    public float Y { get; set; }
}

class Test {
    static void printPts(IPt[] pts) {
        foreach (IPt pt in pts) {
            Console.WriteLine("({0}, {1})", pt.X, pt.Y);
        }
    }

    static void Main() {
        var pts = new Pt[] {
            new Pt { X = 0, Y = 1 },
            new Pt { X = 1, Y = 1 },
            new Pt { X = 1, Y = 0 },
            new Pt { X = 0, Y = 0 }
        };
        printPts(pts);
    }
}