#!/usr/bin/perl

use strict;
use warnings;

my $string = 'i am us$ing moni$ka expressi$on';

my @array = (split /\$/,$string);

my $flag = 0;
my $line = "";
foreach my $element (@array)
{
        if ($flag == 0)
        {
                $line = $element;
                $flag =1;
        }
        else
        {
                $line = $line.'\$'.$element;
        }
}

print $line;