/// <summary>
/// Returns the intersection of this set and that set.</summary>
/// <param name="that"> that the other set</param>
/// <returns>the intersection of this set and that set</returns>
/// <exception cref="ArgumentNullException">if <c>that</c> is <c>null</c></exception>
///
public SET <Key> Intersects(SET <Key> that)
{
if (that == null)
{
throw new ArgumentNullException("called intersects() with a null argument");
}
SET <Key> c = new SET <Key>();
if (this.Count < that.Count)
{
foreach (Key x in this)
{
if (that.Contains(x))
{
c.Add(x);
}
}
}
else
{
foreach (Key x in that)
{
if (this.Contains(x))
{
c.Add(x);
}
}
}
return(c);
}
/// <summary>Returns a random simple digraph containing <c>V</c> vertices and <c>E</c> edges.</summary>
/// <param name="V">the number of vertices</param>
/// <param name="E">the number of vertices</param>
/// <returns>a random simple digraph on <c>V</c> vertices, containing a total
/// of <c>E</c> edges</returns>
/// <exception cref="ArgumentException">if no such simple digraph exists</exception>
///
public static Digraph Simple(int V, int E)
{
if (E > (long)V * (V - 1))
{
throw new ArgumentException("Too many edges");
}
if (E < 0)
{
throw new ArgumentException("Too few edges");
}
Digraph G = new Digraph(V);
SET <Edge> set = new SET <Edge>();
while (G.E < E)
{
int v = StdRandom.Uniform(V);
int w = StdRandom.Uniform(V);
Edge e = new Edge(v, w);
if ((v != w) && !set.Contains(e))
{
set.Add(e);
G.AddEdge(v, w);
}
}
return(G);
}
/// <summary>
/// Returns a random simple DAG containing <c>V</c> vertices and <c>E</c> edges.
/// Note: it is not uniformly selected at random among all such DAGs.</summary>
/// <param name="V">the number of vertices</param>
/// <param name="E">the number of vertices</param>
/// <returns>a random simple DAG on <c>V</c> vertices, containing a total
/// of <c>E</c> edges</returns>
/// <exception cref="ArgumentException">if no such simple DAG exists</exception>
///
public static Digraph Dag(int V, int E)
{
if (E > (long)V * (V - 1) / 2)
{
throw new ArgumentException("Too many edges");
}
if (E < 0)
{
throw new ArgumentException("Too few edges");
}
Digraph G = new Digraph(V);
SET <Edge> set = new SET <Edge>();
int[] vertices = new int[V];
for (int i = 0; i < V; i++)
{
vertices[i] = i;
}
StdRandom.Shuffle(vertices);
while (G.E < E)
{
int v = StdRandom.Uniform(V);
int w = StdRandom.Uniform(V);
Edge e = new Edge(v, w);
if ((v < w) && !set.Contains(e))
{
set.Add(e);
G.AddEdge(vertices[v], vertices[w]);
}
}
return(G);
}
/// <summary>
/// Returns a random simple bipartite graph on <c>V1</c> and <c>V2</c> vertices
/// with <c>E</c> edges.</summary>
/// <param name="V1">the number of vertices in one partition</param>
/// <param name="V2">the number of vertices in the other partition</param>
/// <param name="E">the number of edges</param>
/// <returns>a random simple bipartite graph on <c>V1</c> and <c>V2</c> vertices,
/// containing a total of <c>E</c> edges</returns>
/// <exception cref="ArgumentException">if no such simple bipartite graph exists</exception>
///
public static Graph Bipartite(int V1, int V2, int E)
{
if (E > (long)V1 * V2)
{
throw new ArgumentException("Too many edges for bipartite graphs");
}
if (E < 0)
{
throw new ArgumentException("Too few edges for bipartite graphs");
}
Graph G = new Graph(V1 + V2);
int[] vertices = new int[V1 + V2];
for (int i = 0; i < V1 + V2; i++)
{
vertices[i] = i;
}
StdRandom.Shuffle(vertices);
SET <Edge> set = new SET <Edge>();
while (G.E < E)
{
int i = StdRandom.Uniform(V1);
int j = V1 + StdRandom.Uniform(V2);
Edge e = new Edge(vertices[i], vertices[j]);
if (!set.Contains(e))
{
set.Add(e);
G.AddEdge(vertices[i], vertices[j]);
}
}
return(G);
}
/// <summary>
/// Returns the union of this set and that set.</summary>
///
/// <param name="that"> that the other set</param>
/// <returns>the union of this set and that set</returns>
/// <exception cref="ArgumentNullException">if <c>that</c> is <c>null</c></exception>
///
public SET <Key> Union(SET <Key> that)
{
if (that == null)
{
throw new ArgumentNullException("called union() with a null argument");
}
SET <Key> c = new SET <Key>();
foreach (Key x in this)
{
c.Add(x);
}
foreach (Key x in that)
{
c.Add(x);
}
return(c);
}
/// <summary>
/// Returns a random rooted-out DAG on <c>V</c> vertices and <c>E</c> edges.
/// A rooted out-tree is a DAG in which every vertex is reachable from a
/// single vertex.
/// The DAG returned is not chosen uniformly at random among all such DAGs.</summary>
/// <param name="V">the number of vertices</param>
/// <param name="E">the number of edges</param>
/// <returns>a random rooted-out DAG on <c>V</c> vertices and <c>E</c> edges</returns>
///
public static Digraph RootedOutDAG(int V, int E)
{
if (E > (long)V * (V - 1) / 2)
{
throw new ArgumentException("Too many edges");
}
if (E < V - 1)
{
throw new ArgumentException("Too few edges");
}
Digraph G = new Digraph(V);
SET <Edge> set = new SET <Edge>();
// fix a topological order
int[] vertices = new int[V];
for (int i = 0; i < V; i++)
{
vertices[i] = i;
}
StdRandom.Shuffle(vertices);
// one edge pointing from each vertex, other than the root = vertices[V-1]
for (int v = 0; v < V - 1; v++)
{
int w = StdRandom.Uniform(v + 1, V);
Edge e = new Edge(w, v);
set.Add(e);
G.AddEdge(vertices[w], vertices[v]);
}
while (G.E < E)
{
int v = StdRandom.Uniform(V);
int w = StdRandom.Uniform(V);
Edge e = new Edge(w, v);
if ((v < w) && !set.Contains(e))
{
set.Add(e);
G.AddEdge(vertices[w], vertices[v]);
}
}
return(G);
}
public static void MainTest(string[] args)
{
TextInput StdIn = new TextInput();
SET <string> set = new SET <string>();
// read in strings and add to set
while (!StdIn.IsEmpty)
{
string key = StdIn.ReadString();
if (key.Equals(""))
{
continue;
}
if (!set.Contains(key))
{
set.Add(key);
Console.WriteLine(key);
}
}
}
public static void MainTest(string[] args)
{
TextInput StdIn = new TextInput();
// key = word, value = set of files containing that word
ST <string, SET <string> > st = new ST <string, SET <string> >();
// create inverted index of all files
Console.WriteLine("Indexing files");
string[] allFileNames = FileIndex.GetFileNames(args);
foreach (string filename in allFileNames)
{
Console.WriteLine(" " + filename);
TextInput input = new TextInput(filename);
while (!input.IsEmpty)
{
string word = input.ReadString();
if (!st.Contains(word))
{
st[word] = new SET <string>();
}
SET <string> set = st[word];
set.Add(filename);
}
}
// read queries from standard input, one per line
while (!StdIn.IsEmpty)
{
string query = StdIn.ReadString();
if (st.Contains(query))
{
SET <string> set = st[query];
foreach (string filename in set)
{
Console.WriteLine(" " + filename);
}
}
}
}
public static void MainTest(string[] args)
{
TextInput StdIn = new TextInput();
SET <string> set = new SET <string>();
// read in strings and add to set
TextInput input = new TextInput(args[0]);
while (!input.IsEmpty)
{
string word = input.ReadString();
set.Add(word);
}
// read in string from standard input, printing out all exceptions
while (!StdIn.IsEmpty)
{
string word = StdIn.ReadString();
if (!set.Contains(word))
{
Console.WriteLine(word);
}
}
}
/// <summary>
/// Returns a random simple digraph on <c>V</c> vertices, <c>E</c>
/// edges and (at least) <c>c</c> strong components. The vertices are randomly
/// assigned integer labels between <c>0</c> and <c>c-1</c> (corresponding to
/// strong components). Then, a strong component is creates among the vertices
/// with the same label. Next, random edges (either between two vertices with
/// the same labels or from a vetex with a smaller label to a vertex with a
/// larger label). The number of components will be equal to the number of
/// distinct labels that are assigned to vertices.</summary>
/// <param name="V">the number of vertices</param>
/// <param name="E">the number of edges</param>
/// <param name="c">the (maximum) number of strong components</param>
/// <returns>a random simple digraph on <c>V</c> vertices and
/// <c>E</c> edges, with (at most) <c>c</c> strong components</returns>
/// <exception cref="ArgumentException">if <c>c</c> is larger than <c>V</c></exception>
///
public static Digraph Strong(int V, int E, int c)
{
if (c >= V || c <= 0)
{
throw new ArgumentException("Number of components must be between 1 and V");
}
if (E <= 2 * (V - c))
{
throw new ArgumentException("Number of edges must be at least 2(V-c)");
}
if (E > (long)V * (V - 1) / 2)
{
throw new ArgumentException("Too many edges");
}
// the digraph
Digraph G = new Digraph(V);
// edges added to G (to avoid duplicate edges)
SET <Edge> set = new SET <Edge>();
int[] label = new int[V];
for (int v = 0; v < V; v++)
{
label[v] = StdRandom.Uniform(c);
}
// make all vertices with label c a strong component by
// combining a rooted in-tree and a rooted out-tree
for (int i = 0; i < c; i++)
{
// how many vertices in component c
int count = 0;
for (int v = 0; v < G.V; v++)
{
if (label[v] == i)
{
count++;
}
}
// if (count == 0) System.err.println("less than desired number of strong components");
int[] vertices = new int[count];
int j = 0;
for (int v = 0; v < V; v++)
{
if (label[v] == i)
{
vertices[j++] = v;
}
}
StdRandom.Shuffle(vertices);
// rooted-in tree with root = vertices[count-1]
for (int v = 0; v < count - 1; v++)
{
int w = StdRandom.Uniform(v + 1, count);
Edge e = new Edge(w, v);
set.Add(e);
G.AddEdge(vertices[w], vertices[v]);
}
// rooted-out tree with root = vertices[count-1]
for (int v = 0; v < count - 1; v++)
{
int w = StdRandom.Uniform(v + 1, count);
Edge e = new Edge(v, w);
set.Add(e);
G.AddEdge(vertices[v], vertices[w]);
}
}
while (G.E < E)
{
int v = StdRandom.Uniform(V);
int w = StdRandom.Uniform(V);
Edge e = new Edge(v, w);
if (!set.Contains(e) && v != w && label[v] <= label[w])
{
set.Add(e);
G.AddEdge(v, w);
}
}
return(G);
}
public static void MainTest(string[] args)
{
SET <string> set = new SET <string>();
// insert some keys
set.Add("www.cs.princeton.edu");
set.Add("www.cs.princeton.edu"); // overwrite old value
set.Add("www.princeton.edu");
set.Add("www.math.princeton.edu");
set.Add("www.yale.edu");
set.Add("www.amazon.com");
set.Add("www.simpsons.com");
set.Add("www.stanford.edu");
set.Add("www.google.com");
set.Add("www.ibm.com");
set.Add("www.apple.com");
set.Add("www.slashdot.com");
set.Add("www.whitehouse.gov");
set.Add("www.espn.com");
set.Add("www.snopes.com");
set.Add("www.movies.com");
set.Add("www.cnn.com");
set.Add("www.iitb.ac.in");
Console.WriteLine(set.Contains("www.cs.princeton.edu"));
Console.WriteLine(!set.Contains("www.harvardsucks.com"));
Console.WriteLine(set.Contains("www.simpsons.com"));
Console.WriteLine();
Console.WriteLine("ceiling(www.simpsonr.com) = " + set.Ceiling("www.simpsonr.com"));
Console.WriteLine("ceiling(www.simpsons.com) = " + set.Ceiling("www.simpsons.com"));
Console.WriteLine("ceiling(www.simpsont.com) = " + set.Ceiling("www.simpsont.com"));
Console.WriteLine("floor(www.simpsonr.com) = " + set.Floor("www.simpsonr.com"));
Console.WriteLine("floor(www.simpsons.com) = " + set.Floor("www.simpsons.com"));
Console.WriteLine("floor(www.simpsont.com) = " + set.Floor("www.simpsont.com"));
Console.WriteLine();
// print out all keys in this set in lexicographic order
foreach (string s in set)
{
Console.WriteLine(s);
}
Console.WriteLine();
SET <string> set2 = new SET <string>(set);
Console.WriteLine("Set equality: {0}", set.Equals(set2));
Console.WriteLine("ToString() equality: {0}", set2.ToString().Equals(set.ToString()));
}