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package algs12;
import stdlib.*;
/* ***********************************************************************
* 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
*
*************************************************************************/
public class Counter implements Comparable<Counter> {
private final String name; // counter name
private int count; // current value
// create a new counter
public Counter(String id) {
name = id;
}
// increment the counter by 1
public void increment() {
count++;
}
// return the current count
public int tally() {
return count;
}
// return a string representation of this counter
public String toString() {
return count + " " + name;
}
// compare two Counter objects based on their count
public int compareTo(Counter that) {
if (this.count < that.count) return -1;
else if (this.count > that.count) return +1;
else return 0;
}
// test client
public static void main(String[] args) {
args = new String[] { "2", "10"};
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]);
}
}
}
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