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package algs41;
import stdlib.*;
import algs35.ST;
/* ***********************************************************************
 *  Compilation:  javac SymbolGraph.java
 *  Execution:    java SymbolGraph filename.txt delimiter
 *  Dependencies: ST.java Graph.java In.java StdIn.java StdOut.java
 *  Data files:   http://algs4.cs.princeton.edu/41undirected/routes.txt
 *                http://algs4.cs.princeton.edu/41undirected/movies.txt
 *
 *  %  java SymbolGraph routes.txt " "
 *  JFK
 *     MCO
 *     ATL
 *     ORD
 *  LAX
 *     PHX
 *     LAS
 *
 *  % java SymbolGraph movies.txt "/"
 *  Tin Men (1987)
 *     Hershey, Barbara
 *     Geppi, Cindy
 *     Jones, Kathy (II)
 *     Herr, Marcia
 *     ...
 *     Blumenfeld, Alan
 *     DeBoy, David
 *  Bacon, Kevin
 *     Woodsman, The (2004)
 *     Wild Things (1998)
 *     Where the Truth Lies (2005)
 *     Tremors (1990)
 *     ...
 *     Apollo 13 (1995)
 *     Animal House (1978)
 *
 *************************************************************************/

public class SymbolGraph {
  private final ST<String, Integer> st;  // string -> index
  private final String[] keys;           // index  -> string
  private final Graph G;

  public SymbolGraph(String filename, String delimiter) {
    st = new ST<>();

    // First pass builds the index by reading strings to associate
    // distinct strings with an index
    In in = new In(filename);
    while (in.hasNextLine()) {
      String[] a = in.readLine().split(delimiter);
      for (int i = 0; i < a.length; i++) {
        if (!st.contains(a[i]))
          st.put(a[i], st.size());
      }
    }

    // inverted index to get string keys in an aray
    keys = new String[st.size()];
    for (String name : st.keys()) {
      keys[st.get(name)] = name;
    }

    // second pass builds the graph by connecting first vertex on each
    // line to all others
    G = new Graph(st.size());
    in = new In(filename);
    while (in.hasNextLine()) {
      String[] a = in.readLine().split(delimiter);
      int v = st.get(a[0]);
      for (int i = 1; i < a.length; i++) {
        int w = st.get(a[i]);
        G.addEdge(v, w);
      }
    }
  }

  public boolean contains(String s) {
    return st.contains(s);
  }

  public int index(String s) {
    return st.get(s);
  }

  public String name(int v) {
    return keys[v];
  }

  public Graph G() {
    return G;
  }

  public String toString() {
    StringBuilder s = new StringBuilder();
    String NEWLINE = System.getProperty("line.separator");
    s.append(G.V() + " vertices, " + G.E() + " edges " + NEWLINE);
    for (int v = 0; v < G.V(); v++) {
      s.append(name(v) + ": ");
      for (int w : G.adj(v)) {
        s.append(name(w) + " ");
      }
      s.append(NEWLINE);
    }
    return s.toString();
  }

  public static void main(String[] args) {
    //args = new String[] { "data/movies.txt", "/" };
    args = new String[] { "data/routes.txt", " " };

    String filename  = args[0];
    String delimiter = args[1];
    SymbolGraph sg = new SymbolGraph(filename, delimiter);
    StdOut.println (sg);

    Graph G = sg.G();
    StdOut.println (G);
    while (StdIn.hasNextLine()) {
      String source = StdIn.readLine();
      if (sg.contains (source)) {
        int s = sg.index(source);
        for (int v : G.adj(s)) {
          StdOut.println("   " + v + " " + sg.name(v));
        }
      } else {
        if (!"".equals(source)) StdOut.println(source + " not found");
      }
    }
  }
}