/**
* Returns the cut-of-the-phase. The cut-of-the-phase is a minimum s-t-cut
* in the current graph, where {@code s} and {@code t} are the two vertices
* added last in the phase. This algorithm is known in the literature as
* <em>maximum adjacency search</em> or <em>maximum cardinality search</em>.
*
* @param G the edge-weighted graph
* @param marked the array of contracted vertices, where {@code marked[v]}
* is {@code true} if the vertex {@code v} was already
* contracted; or {@code false} otherwise
* @param cp the previous cut-of-the-phase
* @return the cut-of-the-phase
*/
private CutPhase minCutPhase(EdgeWeightedGraph G, boolean[] marked, CutPhase cp) {
IndexMaxPQ<Double> pq = new IndexMaxPQ<Double>(G.V());
for (int v = 0; v < G.V(); v++) {
if (v != cp.s && !marked[v]) pq.insert(v, 0.0);
}
pq.insert(cp.s, Double.POSITIVE_INFINITY);
while (!pq.isEmpty()) {
int v = pq.delMax();
cp.s = cp.t;
cp.t = v;
for (Edge e : G.adj(v)) {
int w = e.other(v);
if (pq.contains(w)) pq.increaseKey(w, pq.keyOf(w) + e.weight());
}
}
cp.weight = 0.0;
for (Edge e : G.adj(cp.t)) {
cp.weight += e.weight();
}
return cp;
}
// Use this for initialization
void Start()
{
// insert a bunch of strings
string[] strings = { "it", "was", "the", "best", "of", "times", "it", "was", "the", "worst" };
IndexMaxPQ <string> pq = new IndexMaxPQ <string>(strings.Length);
for (int i = 0; i < strings.Length; i++)
{
pq.insert(i, strings[i]);
}
// print each key using the iterator
foreach (string i in pq)
{
print(i + " " + strings[int.Parse(i)]);
}
// increase or decrease the key
for (int i = 0; i < strings.Length; i++)
{
if (Random.Range(0.0f, 1.0f) < 0.5) // Random.uniform() 返回一个随机的范围在[0,1)之间的double类型的数
{
pq.increaseKey(i, strings[i] + strings[i]);
}
else
{
pq.decreaseKey(i, strings[i].Substring(0, 1));
}
}
// delete and print each key
while (!pq.isEmpty())
{
string key = pq.maxKey();
int i = pq.delMax();
print(i + " " + key);
}
// reinsert the same strings
for (int i = 0; i < strings.Length; i++)
{
pq.insert(i, strings[i]);
}
// delete them in random order
int[] perm = new int[strings.Length];
for (int i = 0; i < strings.Length; i++)
{
perm[i] = i;
}
UnSort(perm); // StdRandom.shuffle() 随机打乱指定的object型数组
for (int i = 0; i < perm.Length; i++)
{
string key = pq.keyOf(perm[i]);
pq.delete(perm[i]);
print(perm[i] + " " + key);
}
}