Count occurrences of a substring: Difference between revisions

=={{header|Mirah}}==

<lang mirah>import java.util.regex.Pattern

import java.util.regex.Matcher

#The "remove and count the difference" method

def count_substring(pattern:string, source:string)

(source.length() - source.replace(pattern, "").length()) / pattern.length()

end

puts count_substring("th", "the three truths") # ==> 3

puts count_substring("abab", "ababababab") # ==> 2

puts count_substring("a*b", "abaabba*bbaba*bbab") # ==> 2

# The "split and count" method

def count_substring2(pattern:string, source:string)

# the result of split() will contain one more element than the delimiter

# the "-1" second argument makes it not discard trailing empty strings

source.split(Pattern.quote(pattern), -1).length - 1

end

puts count_substring2("th", "the three truths") # ==> 3

puts count_substring2("abab", "ababababab") # ==> 2

puts count_substring2("a*b", "abaabba*bbaba*bbab") # ==> 2

# This method does a match and counts how many times it matches

def count_substring3(pattern:string, source:string)

result = 0

Matcher m = Pattern.compile(Pattern.quote(pattern)).matcher(source);

while (m.find())

result = result + 1

end

result

end

puts count_substring3("th", "the three truths") # ==> 3

puts count_substring3("abab", "ababababab") # ==> 2

puts count_substring3("a*b", "abaabba*bbaba*bbab") # ==> 2

</lang>