Text processing/Max licenses in use

Text processing/Max licenses in use
You are encouraged to solve this task according to the task description, using any language you may know.

A company currently pays a fixed sum for the use of a particular licensed software package. In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file.

Assume the softwares file faithfully records a checkout event when a copy of the software starts and a checkin event when the software finishes. An example of checkout and checkin events are:

 License OUT @ 2008/10/03_23:51:05 for job 4974
 ...
 License IN  @ 2008/10/04_00:18:22 for job 4974

Save the 10,000 line log file from here into a local file then write a program to scan the file extracting both the maximum licenses that were out at any time, and the time(s) at which this occurs.

APL

Works with: APL2

Translation of: J

      ⍝  Copy/paste file's contents into TXT (easiest), or TXT ← ⎕NREAD
      I  ←  TXT[;8+⎕IO]
      D  ←  TXT[;⎕IO+14+⍳19]
      lu ←  +\ ¯1 * 'OI' ⍳ I
      mx ←  (⎕IO+⍳⍴lu)/⍨lu= max ← ⌈/ lu
      ⎕  ←  'Maximum simultaneous license use is ' , ' at the following times:' ,⍨ ⍕max ⋄ ⎕←D[mx;]
Maximum simultaneous license use is 99 at the following times:
2008/10/03_08:39:34
2008/10/03_08:40:40

C

<lang c>#include <stdio.h>

1. include <stdlib.h>
2. include <string.h>
3. include <sys/types.h>

1. define INOUT_LEN 4
2. define TIME_LEN 20
3. define MAX_MAXOUT 1000

char inout[INOUT_LEN]; char time[TIME_LEN]; uint jobnum;

char maxtime[MAX_MAXOUT][TIME_LEN];

int main(int argc, char **argv) {

 FILE *in = NULL;
 int l_out = 0, maxout=-1, maxcount=0;

 if ( argc > 1 ) {
   in = fopen(argv[1], "r");
   if ( in == NULL ) {
     fprintf(stderr, "cannot read %s\n", argv[1]);
     exit(1);
   }
 } else {
   in = stdin;
 }

 while( fscanf(in, "License %s @ %s for job %u\n", inout, time, &jobnum) != EOF ) {

   if ( strcmp(inout, "OUT") == 0 )
     l_out++;
   else
     l_out--;

   if ( l_out > maxout ) {
     maxout = l_out;
     maxcount=0; maxtime[0][0] = '\0';
   }
   if ( l_out == maxout ) {
     if ( maxcount < MAX_MAXOUT ) {

strncpy(maxtime[maxcount], time, TIME_LEN); maxcount++;

     } else {

fprintf(stderr, "increase MAX_MAXOUT (now it is %u)\n", MAX_MAXOUT); exit(1);

     }
   }
 }

 printf("Maximum simultaneous license use is %d at the following times:\n", maxout);
 for(l_out=0; l_out < maxcount; l_out++) {
   printf("%s\n", maxtime[l_out]);
 }

 if ( in != stdin ) fclose(in);
 exit(0);

}</lang>

Fortran

Works with: Fortran version 90 and later

PROGRAM MAX_LICENSES
  IMPLICIT NONE

  INTEGER :: out=0, maxout=0, maxcount=0, err
  CHARACTER(50) :: line
  CHARACTER(19) :: maxtime(100)

  OPEN (UNIT=5, FILE="Licenses.txt", STATUS="OLD", IOSTAT=err)
  IF (err > 0) THEN
    WRITE(*,*) "Error opening file Licenses.txt"
    STOP
  END IF

  DO 
    READ(5, "(A)", IOSTAT=err) line
    IF (err == -1) EXIT          ! EOF detected
    IF (line(9:9) == "O") THEN
      out = out + 1
    ELSE IF (line(9:9) == "I") THEN
      out = out - 1
    END IF
    IF (out > maxout ) THEN
      maxout = maxout + 1
      maxcount = 1
      maxtime(maxcount) = line(15:33)
    ELSE IF (out == maxout) THEN
      maxcount = maxcount + 1
      maxtime(maxcount) = line(15:33)
    END IF
  END DO
 
  CLOSE(5)
 
  WRITE(*,"(A,I4,A)") "Maximum simultaneous license use is", maxout, " at the following times:"
  WRITE(*,"(A)") maxtime(1:maxcount)
 
END PROGRAM MAX_LICENSES

Output

Maximum simultaneous license use is  99 at the following times:
2008/10/03_08:39:34                                           
2008/10/03_08:40:40

Haskell

import Data.List

main = do
  f <- readFile "./../Puzzels/Rosetta/inout.txt"
  let (ioo,dt) = unzip. map ((\(_:io:_:t:_)-> (io,t)). words) . lines $ f
      cio = drop 1 . scanl (\c io -> if io == "IN" then pred c else succ c) 0 $ ioo 
      mo = maximum cio
  putStrLn $ "Maximum simultaneous license use is " ++ show mo ++ " at:"
  mapM_ (putStrLn . (dt!!)) . elemIndices mo $ cio

J

   NB.  Parse data, select columns
   'I D' =: (8 ; 14+i.19) { ::]"1 L:0 ];._2 ] 1!:1 ::(''"_) <'licenses.txt'
   
   NB.  Calculate number of licenses used at any given time
   lu    =:  +/\ _1 ^ 'OI' i. I
   
   NB.  Find the maxima
   mx    =:  (I.@:= >./) lu
  
   NB.  Output results
   (mx { D) ,~ 'Maximum simultaneous license use is ' , ' at the following times:' ,~ ": {. ,mx { lu
Maximum simultaneous license use is 99 at the following times:
2008/10/03_08:39:34                                           
2008/10/03_08:40:40

MAXScript

fn licencesInUse =
(
    local logFile = openFile "mlijobs.txt"
    local out = 0
    local maxOut = -1
    local maxTimes = #()
	
    while not EOF logFile do
    (
        line = readLine logFile

        if findString line "OUT" != undefined then
        (
            out += 1
        )
        else
        (
            out -= 1
        )

        if out > maxOut then
        (
            maxOut = out
            maxTimes = #()
        )

        if out == maxOut then
        (
            append maxTimes (filterString line " ")[4]
        )
    )
    format "Maximum simultaneous license use is % at the following times:\n" maxOut 

    for time in maxTimes do
    (
        format "%\n" time
    )

    close logFile
)

licencesInUse()

Output

Maximum simultaneous license use is 99 at the following times:
2008/10/03_08:39:34
2008/10/03_08:40:40

OCaml

<lang ocaml>let () =

 let out = ref 0 in
 let max_out = ref(-1) in
 let max_times = ref [] in

 let ic = open_in "mlijobs.txt" in
 try while true do
   let line = input_line ic in
   let io, date, n =
     Scanf.sscanf line
       "License %3[IN OUT] %_c %19[0-9/:_] for job %d"
       (fun io date n -> (io, date, n))
   in
   if io = "OUT" then incr out else decr out;
   if !out > !max_out then
   ( max_out := !out;
     max_times := date :: []; )
   else if !out = !max_out then
     max_times := date :: !max_times;
 done
 with End_of_file ->
   close_in ic;
   Printf.printf
     "Maximum simultaneous license use is %d \
      at the following times:\n" !max_out;
   List.iter print_endline !max_times;

</lang>

Perl

<lang perl>#!/usr/bin/perl -w use strict;

my $out = 0; my $max_out = -1; my @max_times;

open FH, '<mlijobs.txt' or die "Can't open file: $!"; while (<FH>) {

   chomp;
   if (/OUT/) {
       $out++;
   } else {
       $out--;
   }
   if ($out > $max_out) {
       $max_out = $out;
       @max_times = ();
   }
   if ($out == $max_out) {
       push @max_times, (split)[3];
   }

} close FH;

print "Maximum simultaneous license use is $max_out at the following times:\n"; print " $_\n" foreach @max_times;</lang> Example output:

Maximum simultaneous license use is 99 at the following times:
  2008/10/03_08:39:34
  2008/10/03_08:40:40

Python

<lang python>out = 0 max_out = -1 max_times = []

for job in open('mlijobs.txt'):

   if "OUT" in job:
       out += 1
   else:
       out -= 1
   if out > max_out:
       max_out = out
       max_times = []
   if out == max_out:
       max_times.append(job.split()[3])

print "Maximum simultaneous license use is", max_out, "at the following times:" for time in max_times:

   print " ", time</lang>

Example output:

Maximum simultaneous license use is 99 at the following times:
  2008/10/03_08:39:34
  2008/10/03_08:40:40

Ruby

<lang ruby>out = 0 max_out = -1 max_times = []

open('mlijobs.txt') do |file|

 for job in file
   if job.include?("OUT")
       out += 1
   else
       out -= 1
   end
   if out > max_out
       max_out = out
       max_times = []
   end
   if out == max_out
       max_times << job.split[3]
   end
 end

end

puts "Maximum simultaneous license use is #{max_out} at the following times:" for time in max_times

 puts "  #{time}"

end</lang> Example output:

Maximum simultaneous license use is 99 at the following times:
  2008/10/03_08:39:34
  2008/10/03_08:40:40

Tcl

Translation of: Python

set out 0
set max_out -1
set max_times {}

foreach job [split [read [open "mlijobs.txt" "r"]] "\n"] {
    if {[lindex $job 1] == "OUT"} {
        incr out 
    } { 
        incr out -1
    }   
    if {$out > $max_out} {
        set max_out $out
        set max_times {}
    }   
    if {$out == $max_out} {
        lappend max_times [lindex $job 3]
    }   
}

puts "Maximum simultaneous license use is $max_out at the following times:"
foreach t $max_times {
    puts "  $t"
}

Output matches Python