@Override
    public double getCost(int sx, int sy, int dx, int dy)
    {
        final double x = dx - (double) sx;
        final double y = dy - (double) sy;
        return Math.sqrt(x * x + y * y);
    }
@ Override public double getCost ( int sx , int sy , int dx , int dy ) { final double x = dx - ( double ) sx ; final double y = dy - ( double ) sy ; return Math . sqrt ( x * x + y * y ) ; }
/*
Heuristic