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Task/String-matching/Ruby/string-matching.rb

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+p 'abcd'.start_with?('ab') #returns true
+p 'abcd'.end_with?('ab')   #returns false
+p 'abab'.include?('bb')    #returns false
+p 'abab'.include?('ab')    #returns true
+p 'abab'.index('bb')       #returns nil
+p 'abab'.index('ab')       #returns 0
+p 'abab'.index('ab', 1)    #returns 2
+p 'abab'.rindex('ab')      #returns 2