ruby-on-rails - 查找以“a”开头的字符串中的单词数

Question

在 Ruby 中，我想从这个字符串中显示以“a”开头的单词数：an ant hello hint how are you

Answer 1

您可以将正则表达式与扫描一起使用

string.scan(/\ba/).size

Answer 2

p "an ant hello hint how are you".split.count{|word| word.start_with?('a')}
#=> 3

Answer 3

"a asa  a ss sa a a a ass a ".split.select {|w| w[0] == "a"}.size