Java How Can I Display Each Digit of a Four-Digit Integer on a Separate Line in Java?

AI Thread Summary
To create a program that reads a four-digit integer as a string and displays each digit on a new line, the Scanner class can be utilized to capture user input. After prompting the user for a four-digit number, the input can be processed using the charAt method of the String class to access individual characters. A loop can be implemented to iterate through the string, printing each character on a separate line. Additionally, incorporating error checking to ensure the input is a valid four-digit number is suggested for improved functionality. The discussion highlights the importance of understanding string manipulation and user input handling in Java programming.
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Write a program that reads four-digit integer as a string , such as 1998 and then displays it, one digit per line, like so:
1
9
9
8


Attempt:
Scanner keyboard2 = new Scanner (System.in);
String integer2= "Input a 4 digit number:";
System.out.println(integer2);

How do I make it read ? How do I go about this using string method ? I am lost. Thanks
 
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huh...never seen the Scanner class before. Here's the first doc page I found:
http://www.cs.utexas.edu/users/ndale/Scanner.html

Looks like you can call Scanner.next() to get a string from stdin.

Then you could use String.charAt( x ) to get each character for printing. See here:
http://download.oracle.com/javase/1.4.2/docs/api/java/lang/String.html

For extra credit I guess you could do error checking and stuff to make sure you always get a four digit number as input.
 
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How do I implement digits into the split characters ?

Like I type in any four digit number and prints it in a vertical fashion.

Never mind , I got it.
 
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Your integer2 variable is a string instance, which is essentially an array of type char. You can use the charAt method on the string class to get the character at the specified index.

For instance, if integer2 contains the characters '2', '0', '1', and '1', the expression integer2.charAt(2) evaluates to the character value '1'.

You can use a loop to peel off each character in your integer2 variable.
 
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