- Added solutions by Cristina Heredia.

2 files changed, 150 insertions, 0 deletions

diff --git a/challenge-072/cristian-heredia/perl/ch-1.pl b/challenge-072/cristian-heredia/perl/ch-1.pl
new file mode 100644
index 0000000000..59a3a39d1f
--- /dev/null
+++ b/challenge-072/cristian-heredia/perl/ch-1.pl
@@ -0,0 +1,69 @@
+use strict;
+use warnings;
+
+#You are given a positive integer $N (<= 10).
+#
+#Write a script to print number of trailing zeroes in $N!.
+#
+#Example 1
+#Input: $N = 10
+#Output: 2 as $N! = 3628800 has 2 trailing zeroes
+#
+#Example 2
+#Input: $N = 7
+#Output: 1 as $N! = 5040 has 1 trailing zero
+#
+#Example 3
+#Input: $N = 4
+#Output: 0 as $N! = 24 has 0 trailing zero
+
+
+#variables
+my $N;
+my $result = 1;
+my $count = 0;
+my $sentence;
+
+
+requestNumber();
+
+sub requestNumber {
+   
+    print "Please, introduce a number <= 10\n";
+    $N = <>;
+    $N =~ s/\s//g;
+    if ($N =~ /^\d+$/ and $N <= 10) {
+        obtainFactorial();
+    }
+    else {
+        print "That's not a valid number\n";
+        requestNumber();
+    }
+   
+}
+
+sub obtainFactorial {
+   
+    foreach (my $i = 2; $i <= $N; $i++){
+       
+        $result = $result * $i;
+    }
+    $sentence = "$N! = $result";
+    trailingZeros();
+}
+
+
+sub trailingZeros {
+   
+    if ($result =~ /0$/) {
+       
+        chop($result);
+        $count++;
+        trailingZeros();
+    }
+    else {
+        #Output
+        print "$count as ".$sentence." has $count trailing zero\n";
+    }
+   
+}
diff --git a/challenge-072/cristian-heredia/perl/ch-2.pl b/challenge-072/cristian-heredia/perl/ch-2.pl
new file mode 100644
index 0000000000..060d496e82
--- /dev/null
+++ b/challenge-072/cristian-heredia/perl/ch-2.pl
@@ -0,0 +1,81 @@
+use strict;
+use warnings;
+
+#You are given a text file name $file and range $A - $B where $A <= $B.
+#
+#Write a script to display lines range $A and $B in the given file.
+#
+#Example
+#Input:
+#    $ cat input.txt
+#    L1
+#    L2
+#    L3
+#    L4
+#    ...
+#    ...
+#    ...
+#    ...
+#    L100
+#$A = 4 and $B = 12
+#Output:
+#    L4
+#    L5
+#    L6
+#    L7
+#    L8
+#    L9
+#    L10
+#    L11
+#    L12
+
+
+#Must accept three arguments
+if ($#ARGV != 2){
+  die "Error of arguments: ch-2.pl <file_name> <A> <B>";
+}
+
+my $file_name = $ARGV[0];
+my $A = $ARGV[1];
+my $B = $ARGV[2];
+my $count;
+
+#In case is needed to create the file and filing it
+#createFile();
+sub createFile {
+    foreach (my $i=1; $i<=100; $i++){
+        open (F, ">>$file_name") || die "Could not open file: $!\n";
+        print F "L$i\n";
+        close F;
+    }
+}
+
+#First we check that the file exists
+if  ( !-f $file_name) {
+    die "the file $file_name doesn't exist\n";
+}
+
+#We check $A <= $B
+if ($A >= $B) {
+    die "$A isn't smaller that $B\n";
+}
+
+printLines();
+
+sub printLines {
+    
+    open(FILE, $file_name) or die "Could not read from $file_name\n";
+
+    $count = 1;
+    while (<FILE>) {
+        if ($count > $B) {
+            close FILE;
+            exit;
+        }
+        if ($count >= $A) {
+            print $_;
+        }
+      $count++;
+    }
+}
+