package edu.princeton.cs.algs4.ch12;
import edu.princeton.cs.introcs.*;
/*************************************************************************
* Compilation: javac Counter.java
* Execution: java Counter N T
* Dependencies: StdRandom.java StdOut.java
*
* A mutable data type for an integer counter.
*
* The test clients create N counters and performs T increment
* operations on random counters.
*
* % java Counter 6 600000
* 0: 99870
* 1: 99948
* 2: 99738
* 3: 100283
* 4: 100185
* 5: 99976
*
*************************************************************************/
/**
* The <tt>Counter</tt> class is a mutable data type to encapsulate a counter.
* <p>
* For additional documentation, see <a href="/algs4/12oop">Section 1.2</a> of
* <i>Algorithms, 4th Edition</i> by Robert Sedgewick and Kevin Wayne.
*
* @author Robert Sedgewick
* @author Kevin Wayne
*/
public class Counter implements Comparable<Counter> {
private final String name; // counter name
private int count = 0; // current value
/**
* Initializes a new counter starting at 0, with the given id.
* @param id the name of the counter
*/
public Counter(String id) {
name = id;
}
/**
* Increments the counter by 1.
*/
public void increment() {
count++;
}
/**
* Returns the current count.
*/
public int tally() {
return count;
}
/**
* Returns a string representation of this counter
*/
public String toString() {
return count + " " + name;
}
/**
* Compares this counter to that counter.
*/
public int compareTo(Counter that) {
if (this.count < that.count) return -1;
else if (this.count > that.count) return +1;
else return 0;
}
/**
* Reads two command-line integers N and T; creates N counters;
* increments T counters at random; and prints results.
*/
public static void main(String[] args) {
int N = Integer.parseInt(args[0]);
int T = Integer.parseInt(args[1]);
// create N counters
Counter[] hits = new Counter[N];
for (int i = 0; i < N; i++) {
hits[i] = new Counter("counter" + i);
}
// increment T counters at random
for (int t = 0; t < T; t++) {
hits[StdRandom.uniform(N)].increment();
}
// print results
for (int i = 0; i < N; i++) {
StdOut.println(hits[i]);
}
}
}
/*************************************************************************
* Copyright 2002-2012, Robert Sedgewick and Kevin Wayne.
*
* This file is part of algs4-package.jar, which accompanies the textbook
*
* Algorithms, 4th edition by Robert Sedgewick and Kevin Wayne,
* Addison-Wesley Professional, 2011, ISBN 0-321-57351-X.
* http://algs4.cs.princeton.edu
*
*
* algs4-package.jar is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* algs4-package.jar is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with algs4-package.jar. If not, see http://www.gnu.org/licenses.
*************************************************************************/