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POException in thread "main" java.lang.ArrayIndexOutOfBoundsException: 3 at AdjMatrixDigraph.main(AdjMatrixDigraph.java:90)
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copied!<p>In my code I am trying to derive an adjacency matrix, but I'm getting the following exception.</p> <pre><code>Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 3 at AdjMatrixDigraph.main(AdjMatrixDigraph.java:90) </code></pre> <p>AdjMatrixDigraph.java</p> <pre><code>import java.util.Iterator; import java.util.NoSuchElementException; public class AdjMatrixDigraph extends StdOut { private int V; private int E; private boolean[][] adj; // empty graph with V vertices public AdjMatrixDigraph(int V) { if (V < 0) throw new RuntimeException("Number of vertices must be nonnegative"); this.V = V; this.E = 0; this.adj = new boolean[V][V]; } // random graph with V vertices and E edges public AdjMatrixDigraph(int V, int E) { this(V); if (E < 0) throw new RuntimeException("Number of edges must be nonnegative"); if (E > V*V) throw new RuntimeException("Too many edges"); // can be inefficient while (this.E != E) { int v = (int) (V * Math.random()); int w = (int) (V * Math.random()); addEdge(v, w); } } // number of vertices and edges public int V() { return V; } public int E() { return E; } // add directed edge v->w public void addEdge(int v, int w) { if (!adj[v][w]) E++; adj[v][w] = true; } // return list of neighbors of v public Iterable<Integer> adj(int v) { return new AdjIterator(v); } // support iteration over graph vertices private class AdjIterator implements Iterator<Integer>, Iterable<Integer> { private int v, w = 0; AdjIterator(int v) { this.v = v; } public Iterator<Integer> iterator() { return this; } public boolean hasNext() { while (w < V) { if (adj[v][w]) return true; w++; } return false; } public Integer next() { if (hasNext()) { return w++; } else { throw new NoSuchElementException(); } } public void remove() { throw new UnsupportedOperationException(); } } // string representation of Graph - takes quadratic time public String toString() { String NEWLINE = System.getProperty("line.separator"); StringBuilder s = new StringBuilder(); s.append(V + " " + E + NEWLINE); for (int v = 0; v < V; v++) { s.append(v + ": "); for (int w : adj(v)) { s.append(w + " "); } s.append(NEWLINE); } return s.toString(); } // test client public static void main(String[] args) { int V = Integer.parseInt(args[3]); int E = Integer.parseInt(args[1]); AdjMatrixDigraph G = new AdjMatrixDigraph(V, E); StdOut.println(G); } } </code></pre> <p>StdOut.java</p> <pre><code>import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.io.UnsupportedEncodingException; import java.util.Locale; /** * <i>Standard output</i>. This class provides methods for writing strings * and numbers to standard output. * <p> * For additional documentation, see <a href="http://introcs.cs.princeton.edu/15inout">Section 1.5</a> of * <i>Introduction to Programming in Java: An Interdisciplinary Approach</i> by Robert Sedgewick and Kevin Wayne. */ public class StdOut { // force Unicode UTF-8 encoding; otherwise it's system dependent public static final String charsetName = "UTF-8"; // assume language = English, country = US for consistency with StdIn private static final Locale US_LOCALE = new Locale("en", "US"); // send output here private static PrintWriter out; // this is called before invoking any methods static { try { out = new PrintWriter(new OutputStreamWriter(System.out, charsetName), true); } catch (UnsupportedEncodingException e) { System.out.println(e); } } // don't instantiate public StdOut() { } // close the output stream (not required) /** * Close standard output. */ public static void close() { out.close(); } /** * Terminate the current line by printing the line separator string. */ public static void println() { out.println(); } /** * Print an object to standard output and then terminate the line. */ public static void println(Object x) { out.println(x); } /** * Print a boolean to standard output and then terminate the line. */ public static void println(boolean x) { out.println(x); } /** * Print a char to standard output and then terminate the line. */ public static void println(char x) { out.println(x); } /** * Print a double to standard output and then terminate the line. */ public static void println(double x) { out.println(x); } /** * Print a float to standard output and then terminate the line. */ public static void println(float x) { out.println(x); } /** * Print an int to standard output and then terminate the line. */ public static void println(int x) { out.println(x); } /** * Print a long to standard output and then terminate the line. */ public static void println(long x) { out.println(x); } /** * Print a short to standard output and then terminate the line. */ public static void println(short x) { out.println(x); } /** * Print a byte to standard output and then terminate the line. */ public static void println(byte x) { out.println(x); } /** * Flush standard output. */ public static void print() { out.flush(); } /** * Print an Object to standard output and flush standard output. */ public static void print(Object x) { out.print(x); out.flush(); } /** * Print a boolean to standard output and flush standard output. */ public static void print(boolean x) { out.print(x); out.flush(); } /** * Print a char to standard output and flush standard output. */ public static void print(char x) { out.print(x); out.flush(); } /** * Print a double to standard output and flush standard output. */ public static void print(double x) { out.print(x); out.flush(); } /** * Print a float to standard output and flush standard output. */ public static void print(float x) { out.print(x); out.flush(); } /** * Print an int to standard output and flush standard output. */ public static void print(int x) { out.print(x); out.flush(); } /** * Print a long to standard output and flush standard output. */ public static void print(long x) { out.print(x); out.flush(); } /** * Print a short to standard output and flush standard output. */ public static void print(short x) { out.print(x); out.flush(); } /** * Print a byte to standard output and flush standard output. */ public static void print(byte x) { out.print(x); out.flush(); } /** * Print a formatted string to standard output using the specified * format string and arguments, and flush standard output. */ public static void printf(String format, Object... args) { out.printf(US_LOCALE, format, args); out.flush(); } /** * Print a formatted string to standard output using the specified * locale, format string, and arguments, and flush standard output. */ public static void printf(Locale locale, String format, Object... args) { out.printf(locale, format, args); out.flush(); } // This method is just here to test the class public static void main(String[] args) { // write to stdout StdOut.println("Test"); StdOut.println(17); StdOut.println(true); StdOut.printf("%.6f\n", 1.0/7.0); } } </code></pre>

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