Another way, which looks a little nicer using Switch statements 
use warnings;
use strict;
use feature "switch";

my $letter;
given ($ARGV[0]) {
    when ([0..39])   { $letter = 'F' ; }
    when ($_ <= 49)  { $letter = 'E' ; }
    when ($_ <= 59)  { $letter = 'D' ; }
    when ($_ <= 64)  { $letter = 'C' ; }
    when ($_ <= 69)  { $letter = 'C+'; }
    when ($_ <= 74)  { $letter = 'B' ; }
    when ($_ <= 79)  { $letter = 'B+'; }
    when ($_ <= 100) { $letter = 'A' ; }
}

if ($letter) {
    print "The student has gotten a $letter grade for the score of $AR
+GV[0].\n";
}
else {
    print "Please enter a value between 0 and 100\n"; 
}

[download]

UDPATE: Here is the original question before the owner deleted it:

I started perl a few days ago so are there any ways to make this chunk of code more efficient? The user is supposed to input a score and it'll display something like "The student has gotten a A grade for the score of 100."

#!/usr/bin/perl -w

if($ARGV[0] ~~ [0..39]){
    print "The student has gotten a F grade for the score of $ARGV[0].
+";
}elsif($ARGV[0] <= 49) {
    print "The student has gotten a E grade for the score of $ARGV[0].
+";
}elsif($ARGV[0] <= 59) {
    print "The student has gotten a D grade for the score of $ARGV[0].
+";
}elsif($ARGV[0] <= 64) {
    print "The student has gotten a C grade for the score of $ARGV[0].
+";
}elsif($ARGV[0] <= 69) {
    print "The student has gotten a C+ grade for the score of $ARGV[0]
+.";
}elsif($ARGV[0] <= 74) {
    print "The student has gotten a B grade for the score of $ARGV[0].
+";
}elsif($ARGV[0] <= 79) {
    print "The student has gotten a B+ grade for the score of $ARGV[0]
+.";
}elsif($ARGV[0] <= 100) {
    print "The student has gotten a A grade for the score of $ARGV[0].
+";    
}else {
     print "Please enter a value between 0 and 100"; 
}

[download]
Thanks in advance. Victor

In reply to Re: Conditional statement by toolic
in thread conditional statement by victorlai

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