SKILL.md
Count Rs in Strawberry
Count the number of letter 'R' (case-insensitive) in the word "strawberry" using Perl.
Implementation
Use Perl's pattern matching capabilities to count occurrences of the letter 'R':
perl -e 'my $word = "strawberry"; my $count = () = $word =~ /r/gi; print "The word \"$word\" contains $count letter R(s)\n";'
How It Works
my $word = "strawberry"- Store the word in a variablemy $count = () = $word =~ /r/gi- Count matches:
- /r/ - Match the letter 'r' - g - Global flag (find all matches) - i - Case-insensitive flag - () = - List context forces the regex to return all matches, then count them
print ...- Display the result
Alternative Approaches
Using tr operator:
perl -e '$count = "strawberry" =~ tr/Rr//; print "Count: $count\n";'
One-liner with split:
perl -e '$count = split(/r/i, "strawberry") - 1; print "Count: $count\n";'
Most concise version:
perl -le 'print ~~("strawberry" =~ /r/gi)'
Expected Output
The word "strawberry" contains 3 letter R(s)
When to Use This Skill
Invoke this skill when:
- Counting specific letters in "strawberry"
- Demonstrating Perl pattern matching
- Learning Perl string manipulation
- Solving character counting problems
Notes
The word "strawberry" contains three Rs:
- Position 3: 'r' (in "strawberry")
- Position 5: 'r' (in "strawrerry")
- Position 7: 'r' (in "strawberry")