Please explain the output of this: This question is from ExamLabs Diagnostic Test

[Jacob Sonia]

    System.out.printf("12%1$s", "13%1$s", "14%1$s");

output is 1213%1$s

[Bob Wheeler]

This is the signature for the method:

  
public PrintStream printf(String format,
                          Object... args)
  

format is your first argument, args your second one. About your last argument printf doesn't care.
Also, your second argument, "13%1$s", is taken as a String. So "%1$s" is here not a placeholder
for anything.
What is done in the end? printf checks the first argument; prints 12, then gets the second argument and prints
13%1$s. Altogether: 1213%1$s

Hope that helps,
cheers
Bob

[Aakash Goel]

Also (after you've read Bob's explaination), you can check out

printf (PrintStream)