using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Pvc
{
    class Program
    {
        static void Main(string[] args)
        {
            var g = new DependencyGraph();
            g.AddDependency("A", "B");
                g.AddDependency("B", "D"); // circular
                g.AddDependency("B", "E");
                    g.AddDependency("E", "F");
            g.AddDependency("A", "C");
                g.AddDependency("C", "E");
                g.AddDependency("C", "G");
            g.AddDependency("A", "D");
                g.AddDependency("D", "B"); // circular

            var paths = g.GetPaths("A");
        }
    }
}