Maybe a little something like this?

my $string = q{
1. This is just a sample.
2. This is to check 
3. How a set of values 
4. can be replaced by another 
5. set of values and that too 
6. in the most efficient way.
};
my %replacements = (
    '1.' => 'a.',
    '2.' => 'b.',
    '3.' => 'c.',
    '4.' => 'd.',
    '5.' => 'e.',
    '6.' => 'f.',
);

my $regexp = join '|', map quotemeta, keys %replacements;
$string =~ s/($regexp)/$replacements{$1}/g;

print $string;

[download]
perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re: Efficient way to replace a set of values with another set of values by tobyink
in thread Efficient way to replace a set of values with another set of values by darklord_999

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