? Matches zero or one occurrences of the preceding pattern : Regex « Utility Classes « SCJP

1. SCJP
2. Utility Classes
3. Regex

public class MainClass{
  public static void main(String[] argv){
    String str = "ababc";
    
    
    System.out.println(str.split("(ab)?").length);
  }
}

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