Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
Solved

reverse a word using stack

Posted on 2003-11-06
9
898 Views
Last Modified: 2012-08-13
How do reverse a word by using a stack? How many stack should i use?

izzit top into a stack, then already can topAndPop() to print it out?

Stack stk = new ArrayStack();
while(!stk.isEmpty())
System.out.println(stk.topAndPop());
0
Comment
Question by:Rebecca2003
  • 3
  • 2
  • 2
  • +1
9 Comments
 
LVL 86

Expert Comment

by:CEHJ
ID: 9696185
Sounds suspiciously like homework...
0
 
LVL 23

Expert Comment

by:brettmjohnson
ID: 9696217
One stack will do.  The nature (indeed definition) of a stack is "Last In, First Out" (LIFO).
So items are removed from the stack in the reverse order in which they were pushed
onto the stack.  Therein is the mechanism for "reversing the characters in a word".

First, I would use java.util.Stack instead of the Apache ArrayStack class.  You might as
well stick to the standard classes for such trivial problems.  Create the Stack, iterate
over the string, pushing the individual characters on the stack (see java.lang.Character).
After the entire word has been pushed on the stack.  Pop of the characters one at a time,
constructing the new word in reverse order.

0
 
LVL 86

Expert Comment

by:CEHJ
ID: 9696243
...but here are some clues

1. You can only push objects on a Stack
2. Strings are composed of (arrays of) char, so it would be natural for the String class to have methods that reflect this reality
3. The object version of char is Character, and it would be natural for that relation to be reflected in the methods of the Character class
0
Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

 
LVL 14

Accepted Solution

by:
StillUnAware earned 20 total points
ID: 9700212
lets say string s equls to word 'Hello' then
the reverse oder of it is

//stack.java
import java.util.*;

public class stack{
  public static void main(String[] args){
    String s = "Hello";
            Stack stk = new Stack();

    for( int i = 0; i < s.length(); i++ )
              stk.push(new Character(s.charAt(i)));
            s = "";
            while( !stk.empty() )
              s = s + (Character)(stk.pop());
            System.out.println(s);
  }
}
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 9700298
StillUnAware, you are obviously StillUnAware about the fact that the Member Agreement states that we cannot code people's homework
0
 
LVL 14

Expert Comment

by:StillUnAware
ID: 9712720
Don't be so mad :), I want my first expert points. It must be homework, but this one is pretty easy, let it be an example for future exercises,

peace
0
 

Author Comment

by:Rebecca2003
ID: 9714801
.
0
 

Author Comment

by:Rebecca2003
ID: 9714861
No...this's not my homework question, my howework question is actually asking me to write a palindrome program.  At first i dunno whether is suitable to use stack or queue. By now, i user 1 stack n 1 queue to solved my program already. Beisdes this, i also noticed that by using 3 stacks is still work.  That question that i asked is quite easy rite... how can it be a homework? So if like this case, if i cant ask this, i really cant work out my program. Thanx StillUnAware for giving me some idea.
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
servlet example 11 49
spring jars download 1 35
Which non-HTML GUI front end to use with Java? 3 24
Cisco ASA: Java web start no go, asdm launcher no go 3 34
An old method to applying the Singleton pattern in your Java code is to check if a static instance, defined in the same class that needs to be instantiated once and only once, is null and then create a new instance; otherwise, the pre-existing insta…
Introduction This article is the first of three articles that explain why and how the Experts Exchange QA Team does test automation for our web site. This article explains our test automation goals. Then rationale is given for the tools we use to a…
Viewers will learn about arithmetic and Boolean expressions in Java and the logical operators used to create Boolean expressions. We will cover the symbols used for arithmetic expressions and define each logical operator and how to use them in Boole…
This theoretical tutorial explains exceptions, reasons for exceptions, different categories of exception and exception hierarchy.

807 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question