bool std3opt()
{
//do
// {
ret = false;
float best = float.MaxValue;
cTSP_LIST_NODE b1 = null, b2 = null, b3 = null;
l1 = list_tour.First;
l1b = l1.Prev.Prev; //n-1
for (; !l1.Equals(l1b); l1 = l1.Next)
{
t.a = l1.Value;
t.b = l1.Next.Value;
l2b = list_tour.First.Prev; //n-1
l3b = list_tour.First;
for (l2 = l1.Next; !l2.Equals(l2b); l2 = l2.Next)
{
t.c = l2.Value;
t.d = l2.Next.Value;
if (t.d == t.a)
{
break;
}
for (l3 = l2.Next; !l3.Equals(l3b); l3 = l3.Next)
{
t.e = l3.Value;
t.f = l3.Next.Value;
if ((t.swap = Best3optSwap2(/*min+tsp.distance[t.e,t.f]*/)) > 0.0)
{
if (best > gain)
{
best = gain;
best_swap = t;
b1 = l1;
b2 = l2;
b3 = l3;
}
}
} //for
} //for
} //for
if (best < EPSILON)
{
ret = true;
swapcase2(best_swap, b1, b2, b3);
}
//} while (ret);
return(ret);
} //std3opt
bool std3optCandidateSet()
{
ret = false;
l1 = list_tour.First;
l1b = l1.Prev;
for (; !l1.Equals(l1b); l1 = l1.Next)
{
t.a = l1.Value;
t.b = l1.Next.Value;
l2b = l1b.Prev.Prev;
for (i = 0; i < nn; i++)
{
l2 = list_tour.Find(tsp.GetNN_Node(l1.Value, i));
if (l2 == null)
{
throw new NotSupportedException("nodo non trovato");
}
if (l2.Equals(l1))
{
continue;
}
if ((l2.Equals(l1.Next)) || (l2.Next.Equals(l1)))
{
continue;
}
t.c = l2.Value;
t.d = l2.Next.Value;
//da mettere come opzione!!!
//Fast
if ((fast) && (tsp.distance[t.a, t.b] <= tsp.distance[t.b, t.c]))
{
continue;
}
l3 = l2.Next.Next;
min = tsp.distance[t.a, t.b] + tsp.distance[t.c, t.d];
for (; !l3.Equals(l1); l3 = l3.Next)
{
if ((l3.Equals(l1.Next)) ||
(l3.Equals(l2)) || (l3.Equals(l2.Next)) ||
(l3.Next.Equals(l2)))
{
continue;
}
t.e = l3.Value;
t.f = l3.Next.Value;
if ((t.swap = Best3optSwap()) > 0)
{
ret = true;
swapcase1();
if ((t.swap != 5) && (i != 9))
{
i = 0;
}
min = tsp.distance[t.a, t.b] + tsp.distance[t.c, t.d];
}
} //for
} //for
} //for
return(ret);
}
