If you only want the total

my $s = 'fileCapaber';
my $count = () = $s =~ m[(a|b|c)]gi;
print $count;

4
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but the tr/// solution above is easier and quicker.

If you want the individual counts, then you could try this.

print 'Found: ', scalar( () = $s =~ m/($_)/ig), "'${_}'s\n" for qw[a b
+ c]

Found:  2 'a's
Found:  1 'b's
Found:  1 'c's
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