01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
package algs24;
import stdlib.*;
import algs12.Transaction;
import algs13.Stack;
/* ***********************************************************************
* Compilation: javac TopM.java
* Execution: java TopM M < input.txt
* Dependencies: MinPQ.java Transaction.java StdIn.java StdOut.java
* Data files: http://algs4.cs.princeton.edu/24pq/tinyBatch.txt
*
* Given an integer M from the command line and an input stream where
* each line contains a String and a long value, this MinPQ client
* prints the M lines whose numbers are the highest.
*
* % java TopM 5 < tinyBatch.txt
* Thompson 2/27/2000 4747.08
* vonNeumann 2/12/1994 4732.35
* vonNeumann 1/11/1999 4409.74
* Hoare 8/18/1992 4381.21
* vonNeumann 3/26/2002 4121.85
*
*************************************************************************/
public class TopM {
// Print the top M lines in the input stream.
public static void main(String[] args) {
args = new String[] { "5" };
StdIn.fromFile ("data/tinyBatch.txt");
int M = Integer.parseInt(args[0]);
MinPQ<Transaction> pq = new MinPQ<>(M+1);
while (StdIn.hasNextLine()) {
// Create an entry from the next line and put on the PQ.
String line = StdIn.readLine();
Transaction transaction = new Transaction(line);
pq.insert(transaction);
// remove minimum if M+1 entries on the PQ
if (pq.size() > M)
pq.delMin();
} // top M entries are on the PQ
// print entries on PQ in reverse order
Stack<Transaction> stack = new Stack<>();
for (Transaction transaction : pq)
stack.push(transaction);
for (Transaction transaction : stack)
StdOut.println(transaction);
}
}
|