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Java Java Arrays Iteration Looping Like These Programmers

I want a solution to this problem.

I am getting :
Bummer: java.util.IllegalFormatConversionException: d != java.lang.String (Look around Formatter.java line 4302)

public class Programmers {

  public void printMenu() {
    String[] programmers = {
            "Yukihiro Matsumoto",
            "David Nolen",
            "Grace Hopper",
            "Linus Torvalds",

    System.out.println("Choose a programmer:");
    // TODO: Print out a menu by looping through the programmers array.
      The menu should be in the form of (each on a line of its own, starting with 1):
      1. Yukihiro Matsumoto
      2. David Nolen
    for(int i=0; i<programmers.length; i++){
    System.out.printf("%d. %d %n",i+1,programmers[i]);



1 Answer

Jason Anders
Jason Anders
Treehouse Moderator 145,857 Points

Hi Ajay Shah

The Community really is a place to come and just "give out solutions," as this does not foster a productive learning environment. However, it is a place to come for assistance in finding the errors and helping to create the correct code.

Your code is syntactically correct, but one thing was overlooked. In the formatted string being output, there is an Integer value and a String value.
%d is correct for the Integer, but %d will not work for the String as it is specifically meant for Integers. This is why you are receiving the IllegalFormatConversionException error, as the compiler cannot convert the String to fit into the Integer placeholder. Just replace that 2nd %d with the place holder used for Strings and the code will work.

Keep Coding! :) :dizzy: