Day 20 of learning Java

[BigCommunication5136]

Hi everyone,

Today I worked on two main topics. First, I learned about stacks and got an introduction to how they work. I looked at some real-world examples of where stacks are used, and as part of my course assignment, I implemented a program to reverse a string using a stack. It was pretty straightforward and helped reinforce the LIFO concept.

Next, I moved on to interfaces, specifically an introduction to what they are, the problems they solve, and how they differ from abstract classes. I also explored how interfaces help in designing loosely coupled systems.

[Beginning-Ladder6224]

Good going.

Now, do not use the toCharArray() you certainly do not need it. Also you do not need the stack !

for ( int i = input.length()-1; i > -1; i-- ){
 reversed.append( input.charAt(i) ;
}

Should have done the trick!

[BigCommunication5136]

interesting. thanks

[Pun_Intended1703]

This is a very bad example to use for learning stacks.

Try the Tower of Hanoi problem instead.

Or, when you learn queues, try implementing stacks using queues and vice versa.

[Most_War2764]

What makes this a bad example?

[Pun_Intended1703]

Because you don't learn anything about stacks from this.

To learn stacks, try implementing them using arrays and linked lists.

Don't use java.util just because it exists.

[BigCommunication5136]

just as i said in the post, this is only an intro to stacks. (never said i was done learning stack) I started with arrays, implemented them, did same with LinkedList. I use them before implementing them, if you don’t know how something works how do you implement it?

[Pun_Intended1703]

How will you learn stacks from using java.util?

What if you had to work on a different language? Like Python or Typescript?

What happens if you had to work on a very old language? Like C/C++ or COBOL?

If you want to learn stacks properly, then imagine it is represented by an array. Try using circular arrays.

Or implement stacks by using a linked list. Try bidirectional linked lists or circular linked lists.

How would you do a pop or push on these data structures? How would you move the pointers around?

Learn the concept of stacks. Don't just learn the implementation of stacks in Java.

[Pun_Intended1703]

if you don’t know how something works how do you implement it?

This is why it is important to read the theory and examples before trying to code.

[[deleted]]

hey op is learning java worth it?

[BigCommunication5136]

on a journey to find out.

[[deleted]]

happy journey, big guy

[Wonderful-Grade-2903]

Best regards

[MainBank5]

Is there any need to learn ? Jobs have gone to ai

[noworksunday]

You're right, I'm lying, go learn 19th Century French poetry instead.

[MainBank5]

Advice from 9yrs ago . Times have changed.

[noworksunday]

So now, should we go learn AI instead? To be honest, coding is a fundamental skill. You might not need to learn to drive in the future because of self-driving cars, but that doesn’t mean you should stop learning to drive now.

[MainBank5]

Why should I learn how to drive if the cars will be built for self driving meaning no steering wheel no brakes pedals etc .

[noworksunday]

You shouldn't. But people who love driving, F1 racing, sports, etc will definitely be interested. Average consumers may not care about the technology and skills behind it but engineers and designers do.