Just iterate the combinations of words from the string:

#! perl -slw
use strict;

# my %hash = ...;
my $str = 'Hi this is the sample string for string search';
my @words = split ' ', $str;

for my $start ( 0 .. $#words - 1 ) {
    for my $end ( $start .. $#words ) {
        print "Lookup: ", join ' ', @words[ $start .. $end ];
    }
}

__END__
C:\test>1001794
Lookup: Hi
Lookup: Hi this
Lookup: Hi this is
Lookup: Hi this is the
Lookup: Hi this is the sample
Lookup: Hi this is the sample string
Lookup: Hi this is the sample string for
Lookup: Hi this is the sample string for string
Lookup: Hi this is the sample string for string search
Lookup: this
Lookup: this is
Lookup: this is the
Lookup: this is the sample
Lookup: this is the sample string
Lookup: this is the sample string for
Lookup: this is the sample string for string
Lookup: this is the sample string for string search
Lookup: is
Lookup: is the
Lookup: is the sample
Lookup: is the sample string
Lookup: is the sample string for
Lookup: is the sample string for string
Lookup: is the sample string for string search
Lookup: the
Lookup: the sample
Lookup: the sample string
Lookup: the sample string for
Lookup: the sample string for string
Lookup: the sample string for string search
Lookup: sample
Lookup: sample string
Lookup: sample string for
Lookup: sample string for string
Lookup: sample string for string search
Lookup: string
Lookup: string for
Lookup: string for string
Lookup: string for string search
Lookup: for
Lookup: for string
Lookup: for string search
Lookup: string
Lookup: string search

[download]

Where words (or word combinations) appear twice in the string, they will be looked up twice, but that will be faster than de-duplicating the combinations.

Whether that is a problem will depend on whether you consider the same word or phrase appearing in different places duplicates or not; and what you are doing with the information you are generating.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

RIP Neil Armstrong

In reply to Re: String Search by BrowserUk
in thread String Search by Sishanth

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