I would use splice to remove a set from the beginning of the array and push it onto a new array. Repeat 10 times. push your new element onto the new array. Repeat until original array is exhausted. 

use strict;
use warnings;
use Data::Dumper; 

my @array = ("create", "mount", "remove","create", "mount", "remove","
+create", "mount", "remove","create", "mount", "remove","create", "mou
+nt", "remove","create", "mount", "remove","create", "mount", "remove"
+,"create", "mount", "remove","create", "mount", "remove","create", "m
+ount", "remove","create", "mount", "remove","create", "mount", "remov
+e","create", "mount", "remove","create", "mount", "remove","create", 
+"mount", "remove","create", "mount", "remove","create", "mount", "rem
+ove","create", "mount", "remove","create", "mount", "remove","create"
+, "mount", "remove");

my $nset = 3;
my $every = 10;
my $newelement = "newelement";

my @newarray;
while( @array ) {                            
  for( 1..$every ) {                         # for 10 times
    push @newarray, splice @array, 0, $nset; # push a set onto new arr
+ay
  }
  push @newarray, $newelement;               # add the new element
}

print Dumper \@newarray;

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In reply to Re: Adding an new element after every 5th element in array by hdb
in thread Adding an new element after every 5th element in array by dvinay

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