use Data::Dumper;

use strict;

my @keywords = qw(auto continue enum if short break switch volatile de
+fault extern int signed typedef while case do float long sizeof union
+ char double for register static unsigned const else goto return stru
+ct void);
my $keywords_re = join '|', @keywords;

my $file = '/home/vikash/maya/new.c';

open my $fh, $file or die $!;

my %keywords;
while (<$fh>) {
    while (m{\b($keywords_re)\b}g) {
        $keywords{$1}++;
    }
}

print Dumper(\%keywords);
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