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Java Java Basics Perfecting the Prototype Looping until the value passes

Posted by vikster
vikster
1,991 Points

I don't quite understand this...could you explain the task in a different way maybe?

I am confused on what to do inside the do while loop and how to prompt for an answer afterward

Example.java 
// I have initialized a java.io.Console for you. It is in a variable named console.
String response; 
do{
  console.readLine("Do you Understand do while loops?");
} while(response);

3 Answers

Sjors Theuns
Sjors Theuns
6,091 Points
Sjors Theuns
Sjors Theuns
6,091 Points

Hi Viktoria,

the first task of this challenge is to simply store the value in a string called response, so there is no do...while loop needed at this point. Try:

String response = console.readLine("Do you Understand do while loops?");

The for the second task of this challenge you do need to use a do...while loop for checking the giving answer. Like so:

String response; 
do {
  response = console.readLine("Do you Understand do while loops?");
} while(response.equalsIgnoreCase("no"));

And finally for the last task, just add a simple console.printf statement:

String response; 
do {
  response = console.readLine("Do you Understand do while loops?");
} while(response.equalsIgnoreCase("no"));

console.printf("Because you said %s, you passed the test!", response);

I hope that you can understand what I wrote here. Because simply copying and pasting would pass the challenge, but it is also important to understand how it works ("Do you Understand do while loops?" ;-) )

vikster
vikster
1,991 Points
vikster
vikster
1,991 Points

Yes I understand! I was confused on why you put the response.equalsIngnoreCase directly after the while instead on within {} like you do with the "do" part of the loop.

Sjors Theuns
Sjors Theuns
6,091 Points
Sjors Theuns
Sjors Theuns
6,091 Points

Hi Viktoria,

You can also do it inside the loop. For this you need to declare a boolean variable, see here:

String response;
boolean isInvalid;
do {
  response = console.readLine("Do you Understand do while loops?");
  isInvalid = response.equalsIgnoreCase("no");
} while(isInvalid);

console.printf("Because you said %s, you passed the test!", response);

This way the loop keeps going as long as the boolean value is true. In this case if you enter the word "no". The outcome will be the same as my previous example. They are just different approaches.

Hope this helps.