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

1. my $word = "strawberry"

   - Store the word in a variable

2. my $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

3. 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")