using System;

namespace DistanceTask
{
	public static class DistanceTask
	{
        // Расстояние от точки (x, y) до отрезка AB с координатами A(ax, ay), B(bx, by)
        public static double Distance(double x1, double x2, double y1, double y2)
        {
            return Math.Sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
        }


        public static double GetDistanceToSegment(double ax, double ay, double bx, double by, double x, double y)
        {
            if (ax == ay && bx == by)
            {
                return Distance(x, ax, y, ay);
            }
            double ab = Distance(bx, ax, by, ay);
            double ac = Distance(x, ax, y, ay);
            double bc = Distance(x, bx, y, by);
            if (Math.Pow(ab, 2) + Math.Pow(ac, 2) <= Math.Pow(bc, 2) || Math.Pow(ab, 2) + Math.Pow(bc, 2) <= Math.Pow(ac, 2))
                return Math.Min(ac, bc);
            double p = (ab + ac + bc) / 2;
            double h = (2 * Math.Sqrt(p * (p - ab) * (p - ac) * (p - bc))) / ab;
            return h;
        }
    }
}