Forem: Muhammad Ichsanul Fadhil

Free Platform to Evaluate and Improve Your Coding Skills

Muhammad Ichsanul Fadhil — Thu, 30 Oct 2025 01:31:26 +0000

You’ve probably noticed how everything these days seems to revolve around tech, right? Coding isn’t just something only professional developers do anymore — it’s becoming a super useful skill for everyone. Whether you’re a student trying to learn something new, a freelancer building your own website, or just a curious person who loves tech, knowing how to code can seriously boost your game.

The cool part? You don’t need to spend a ton of money on fancy online courses or bootcamps to see how good you are. There are plenty of free tools out there that let you test and improve your programming skills. One of my favorites is budibadu.com i just found it today and i think they are is very cool because free haha 😄

💡 What Are Coding Challenges?

A coding challenge is an interactive exercise or problem designed to test your understanding of programming logic, syntax, and algorithms. These challenges often require you to write code to solve a specific task, such as sorting data, building a small program, or fixing a piece of buggy code.

Coding challenges simulate real-world scenarios — just like the ones developers face at work. They can range from simple problems for beginners (like reversing a string) to advanced algorithmic puzzles used in technical interviews at companies like Google or Microsoft.

For example as you can see for this problem Pier Ticket Window Time
you will see the problem explanation on left side then a box for like vscode on right side, as a developer you need to analyze the problem find the best solution and can make code that produce output that same like test case provided.

Here summary of that coding challenge.

Before a lantern parade, several ticket windows serve guests at different speeds — each window takes a fixed number of minutes to process one guest. All windows work simultaneously. The goal is to find the minimum time (in minutes) needed for all windows combined to serve a given number of guests.

You’re given:

An array rates, where each element represents how many minutes a specific window needs to serve one guest.
An integer guests, the total number of people waiting.

Our task:

Find the smallest integer t such that the total number of guests served by all windows within t minutes is at least equal to guests. Use binary search over time to efficiently find this minimum value.

Let's solve that problem with languange python.

Here the code template that given from platform, we just fill it with the code, no need to write entrypoint function on that answer just complete the existing function.

from typing import List

def pier_ticket_window_time(rates: List[int], guests: int) -> int:
    """
    Return the minimum minutes needed to serve all guests.
    """
    # If there are no guests, no time is needed
    if guests == 0:
        return 0

    # Define the search range
    left, right = 0, min(rates) * guests  # upper bound (fastest window serves all)

    # Binary search to find minimum time
    while left < right:
        mid = (left + right) // 2

        # Calculate total guests served in 'mid' minutes
        served = sum(mid // rate for rate in rates)

        # If enough guests are served, try shorter time
        if served >= guests:
            right = mid
        else:
            left = mid + 1

    return left

Run that code on platform and you will get see this image, this meand you have solved one problem👌

Conclusion

And that’s it! Pretty fun, right? 😄 Coding challenges like this one are such a great way to sharpen your skills, you learn how to think logically, write clean code, and actually see your results. What I like from budibadu.com is all problem is free and the problems also unique.

I think that’s enough for today. I hope this little sharing helps you out! Thanks for reading, and see you again in my next post

Exploring All Javascript Array Methods

Muhammad Ichsanul Fadhil — Sat, 25 Nov 2023 11:36:28 +0000

In this article I will discuss various methods that I often encounter which are used to process data with array data types, please read, study and practice so you don't forget.

So let's get started.

Map

At this article i will talk about one method in javascript that very often used in commonly, that's is map() so let's go..

This method by the way including methods that have been around for a long time in JavaScript, they were added during the ES5 version of JavaScript around 2009.

We can use this method to populate new array based on custom condition in your array.

Example i have array like this.

let a = [2,3,4,2,1,7,8,11]
let b = a.map(v => {
  return v * 10
})

// [20, 30, 40, 20, 10, 70, 80, 110]

At above I created a new array where it is created with each element of the variable a multiplied by 10.

Or we can add and delete field inside element of object.

let a = [
  {
  count: 10,
  name: 'Muhammad ichsan'
  },
  {
  count: 119,
  name: 'Ichsan'
  }
]

// delete field object element
let b = a.map(v => {
  return {
    count: v.count
  }
})

// add field object element
let c = a.map(v => {
  return {
    ...v,
    date: 'now'
  }
})

Here you can also do conditioning on the return value, in the example below, it will return all fields on the object if the count value on the element is not 119, if it is 119 then it will only return the count field.

let b = a.map(v => {
  if (v.count == 119){
    return {
      count: v.count
    }
  }

   return {
      ...v
   }
})

Array map have 3 argumen on callback, there are is (element, index_of_element, its array).

Concat

array.concat() is used for combining two array, this method not manipulate first and second array but this will be returning new array with element's from first array plus second array.

let arr1 = [1,2,3]
let arr2 = [4,5,6]

let arr3 = arr1.concat(arr2)
// [1,2,3,4,5,6]

CopyWithin

copyWithin() method will be copy range of element into particular index of array. Example i want move 'd','e', and 'f' into start from first index array.

const array1 = ['a', 'b', 'c', 'd', 'e', 'f'];
console.log(array1.copyWithin(0, 3, 6));
// ['d', 'e', 'f', 'd', 'e', 'f']

Format this method like this array.copyWithin(targetindex, startindexelement, endindexelement). Noted for endindexelement, if you choose example startindex is 3 and endindexelement 6 they will be copy element from index 3 until 5 not 6.

Every

every() method basically will be return true if looping elemen condition also return true all, if there is one loop element that returns a false value then the result of every method will still be false.

Example at here i want check whether all e elements in my array value exceed 100 or not.

const array1 = [111, 310, 119, 129, 110, 113];
console.log(array1.every(v => v > 100));
// true

If there is just one loop that does not produce true, then every method will produce false.

const array1 = [111, 310, 119, [9,4], 110, 113];
console.log(array1.every(v => v > 100));
// false

Just like other array loops, in the callback you will also get 3 arguments, namely (value, index, array).

Filter

Next is filter(), this method actually have same mechanisme with map(). Both of them will be returning new array based on conditional in looping.

But of course there are differences between the two, as we know that the resulting map array will have the same number of elements as the initial array. This is different from filters, where we can delete elements that do not match the conditions we set.

The behavior of elements that do not match the conditions is that the map will fill the element with undefined or change its value while the filter will completely disappear.

const array = [111, 310, 119, 99, 110, 113];

const array1 = array.filter(v => v > 100);
const array2 = array.map(v => {
  if (v > 100){
    return v
  }
});
console.log(array1)
// [111, 310, 119, 110, 113]
console.log(array2)
// [111, 310, 119, undefined, 110, 113]

Flat

The flat() method of Array instances creates a new array with all sub-array elements concatenated into it recursively up to the specified depth.

flat method accept one parameter thats is for define depth array that we want to be flatted.

let arr = [1, 2, [3, 4, [5, 6]]];
console.log(arr.flat())
// [1, 2, 3, 4, [5,6]]

This method by the way not suporting to object element, if you want flat an array inside object element maybe you can iterate first the element using map or forEach.

FlatMap

Actually this method is a combination of map and flat with a depth of 1, what this method does is do the map first then if there is a 1 level nested array then it will run flat.

flatMap() will be running like this.

const arr = [1, 2, 1,] ;

const result = arr.map(v => [v, 100]).flat();
const result = arr.flatMap(v => [v, 100]);

ForEach

A method that must be familiar to your ears, the forEach() method is used to loop elements in an array with the same parameters, namely element, index and array.

In contrast to the map in foreach, we cannot manipulate the elements with returns, to change the value of the element we can use an array of arguments and indexes.

This below code i change value to 199 at element with have value 5.

let y = [5,4,4,4,4,4]

y.forEach((v, i, arr) => {
  console.log(v)
  console.log(i)
  console.log(arr)

  if (v == 5){
    arr[i] = 199
  }
})

So what's the difference with a map?

The difference is that in map we have to use return to manipulate elements or return elements, while in foreach we don't need return at all in the code block.

Reduce

This method is actually the same as foreach and map, the difference is that there is one more parameter given to the callback, namely the accumulator.

accumulator is value that be returned from previous looping, for first looping value of accumulator is first index of array. And for first value for current value in first looping is element at index 1.

The structure for this method especially in parameter like this.

let y = [5,6,4]

y.reduce((pv, cv, ci, arr) => {
  console.log(pv)
  console.log(cv)
  console.log(ci)
  console.log(arr)

  return 9
})

pv = accumulator
cv = current value
ci = current index
arr = its array

Its only shortname that i given alone, you can give custom name of parameter with freely.

Slice

Slice will receive 2 parameters, the first is the start index and the second is the end index of the array. This method will return an array with the results of deleting elements based on the start and end index that we set.

If we not pass end index then the slice method will cut elements at index less than the start index. In the example below, I enter 3 as the start index, and what happens is that the slice will cut elements at index 2, 1, and 0.

const animals = ['ant', 'bison', 'camel', 'duck', 'elephant'];
console.log(animals.slice(3));
// ['duck', 'elephant']

We can also enter a negative value in the start index. What happens is that elements in the array will be left for the right side, for example I enter -2 below, then the result is that I get the first 2 elements from the last.

const animals = ['ant', 'bison', 'camel', 'duck', 'elephant'];
console.log(animals.slice(-2));
// ['duck', 'elephant']

For example, here I will take the camel and duck values using the end index. Both are located at index 2 and 3, therefore I set the start index to 2 which will take the element at index 2 and set the end index to 4 because the limit is less than 4.

const animals = ['ant', 'bison', 'camel', 'duck', 'elephant'];
console.log(animals.slice(2,4));

Splice

Different from slice, this splice method is more precisely used to replace elements in a certain index range. The syntax like this.

splice(start, deleteCount, item1, item2, /* …, */ itemN)

Example I want to replace the elements at the first index with the 3 values that I define below.

const months = ['Jan', 'March', 'April', 'June'];
months.splice(1, 2, 'May', 'December', 'November');
// ["Jan", "May", "December", "November", "June"]

We can also use this to delete elements at a certain index by not entering the value that will be included in replace in the third argument.

Some

The some() method of Array instances tests whether at least one element in the array passes the test implemented by the provided function. It returns true if, in the array, it finds an element for which the provided function returns true; otherwise it returns false. It doesn't modify the array.

This is the opposite of the every method which requires all looping elements to produce true values.

const array = [1, 2, 3, 121, 5];
const even = (v) => v > 100;

console.log(array.some(even));
// true

Shift & Pop

Shift and Pop are both used to delete one element in an array. Shift is used to delete the first element, while pop is used to delete the last element.

These two methods do not produce a new array but instead manipulate the array used.

const array = [1, 2, 3];
array.shift();
// [2,3]
array.pop();
// [2]

ChangeNotifier without Provider? Lets Try

Muhammad Ichsanul Fadhil — Mon, 27 Feb 2023 01:13:12 +0000

Example we have a class that belong to ChangeNotifier, like this.

class AppNotifier with ChangeNotifier{
  String text = "Kolak";

  setText(){
    this.text = "Berubah";
    notifyListeners();
  }

  getText(){
    return this.text;
  }
}

That's is very simple class that implement the ChangeNotifier, with that now AppNotifier become to be a informant.

If we use Provider package we will must to create a provider as a wrapper to parent for all the widget that have data change's.

class MyApp extends StatelessWidget {

  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Suhu Converter',
      home: ChangeNotifierProvider(
        create: (ctx) => AppNotifier(),
        child: Scaffold(
          appBar: AppBar(
            title: Text("App Ku"),
          ),
          body: Consumer<AppNotifier>(
            builder: (ctx, data, _){
              return Text(data.getText());
            },
          ),
          floatingActionButton: Consumer<AppNotifier>(
            builder: (ctx, data, _){
              return FloatingActionButton(
                child: Text("Ubah"),
                onPressed: (){
                  data.setText();
                },
              );
            },
          )
        ),
      )
    );
  }
}

We can see at the above code the ChangeNotifierProvider() method wrapped all widget that will be consume data from ChangeNotifier class thats is AppNotifier.

Every widget that will be consume data to AppNotifier class must be wrapped to Consumer class. At the end we can get the flow like this.

Thats is very simple flow to explanate the concept of ChangeNotifier with Provider works together.

ChangeNotifier without Provider

So what happen when we create a ChangeNotifier without we consume and trigger the data change without provider package?

Yes we must use a StatefulWidget 😉 Let's Try....

First we need to convert our widget to stateful and create a state class for that.

class MyApp extends StatefulWidget{
  State<MyApp> createState() => MyAppState(); 
}

class MyAppState extends State<MyApp> {

  Widget build(BuildContext context) {
   .....
  }
}

Next we must register AppNotifier into our state...

class MyAppState extends State<MyApp> {

  var notifier = AppNotifier();

  void initState(){
    notifier.addListener((){
      print("Run");
      setState(() {
      });
    });
    super.initState();
  }

  Widget build(BuildContext context) {
    ...
  }
}

Lastly we can use the method from AppNotifier easily without must to wrapper of any class again.


  var notifier = AppNotifier();

  .....

  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text("App Main"),
        ),
        body: Text(notifier.getText()),
        floatingActionButton: FloatingActionButton(
          child: Text("Ubah"),
          onPressed: (){
            notifier.setText();
          },
        ),
      )
    );
  }
}

And done it's simple right??

Why developer need Git?

Muhammad Ichsanul Fadhil — Wed, 15 Feb 2023 02:07:01 +0000

Git, git and git again...

What is this git? why do we as developer should be mastering this technology? so what if we don't use git? will there be a natural disaster 😓

Let's take at least 5 minutes to understand why we use git here.

So let's go.....

Before git created

Git was created by Linus Torvalds in 2005 with the aim of recording every version (change) of Linux, as it is known that git was created by him at the same time as the creation of the Linux kernel.

A project will definitely be done by several people with different tasks, some are working on features A, B, C and bla bla. So the question arises, how can a group work together in working on a project ❓

There are several options used by several teams working on a project before git existed.

use a flashdisk
take turns working on the same computer
send any changes by any intermediary
and various other complicated methods

For example, a team will work on project A with 3 members.

Before git they would have worked with the following method, sorry I'm using an analogy in the form of diagrams, because I can't make good design 😅

From the flow above, we can see how a team with many members works on a project.

In the flow above there are 3 people namely, Andi, Jaka and Rizki where these three people will definitely work on different features.

In a project (before there was git) we would definitely have a role that would review any changes submitted by team members. From the flow above, Jaka is the one who acts as a reviewer as well as the main project holder, if in git Jaka's role is to manage the main branch.

Jaka's job....

Jaka's job is that he must check the code sent by other members, whether changing the code will not result in an error when the program is run, is it as expected or not.

If the changes sent by members have been reviewed by Jaka and the changes are okay, then jaka will merge the code into the main work, this is often referred to as merge in git.

Flow like that is what a team will do repeatedly until the project is finished, each team will send their changes to main (Jaka), Jaka will check these changes and he will combine them into the main work.

This flow is actually commonplace to do, but when we face complex projects, we will definitely experience some very troublesome problems if we have to solve it with a flow like this.

For example Jaka deleted some codes but at one point it turned out that the code was needed again...

Now the only way is, Rizki and Andi have to copy the files for every change that he will send to Jaka. Imagine if there were 1000 changes made by them, of course he would also copy the edited files for 1000 😩

So therefore Git created, one of the VCS software (Version Control System). From the name alone, surely we already know that git is used to control the version of a system, are you still confused? ok let's discuss git directly 😊

Git and it's functions

We can solve the previous problem with git, how? ok let's discuss.

Replacing Jaka's role with branch

Jaka's role here is the one who has control over the main work, he who checks the code sent by other members, he who will deploy the application in the end, and so on.

In git we can find the term Branch, where everyone must have their own branch, and each branch has different tasks.

Saving changes with staging area

Git has 3 areas, namely the working area, staging area, and repository.

The working area is the folder where you are currently working, the staging area is an area where you can save the changes you made before. By entering our files into the staging area, we will be able to track our files further for any changes we make.

This can replace the manual method of copying files every time you make a change.

Closing

Okay, that's all for this article, I hope you can understand better why and what are the reasons we use git. In the next article I will discuss about Git technology in depth, starting from commit, pull, branch, and merge.

See you in the next article 🔥

Fetch linkedin data user easily with linkedin api & python

Muhammad Ichsanul Fadhil — Mon, 06 Feb 2023 01:37:04 +0000

In this article i will show to you how fetch a linkedin user's profile an anything related to data linkedin user with Linkedin API and Python.

So let's go 😄

Setup

Before start in coding we must install the depedency and other tool, there are is.

Python >= 3.6
pip3

If you have done with both of tool next we can install the package with this command.

pip3 install linkedin-api~=2.0.0a

So the library was succesfully installed and now we can use them.

Add package and credentials

First we must fill the credentials account for login, and dont remember to import the package into our python file.

from linkedin_api import Linkedin

linkedin = Linkedin("youremaillinkedin", "yourpasslinkedin")

Now variable linkedin will become to object that can we use for any action with in.

Uses

So lets with simple example.

Get all user's information

from linkedin_api import Linkedin

linkedin = Linkedin("youremail", "yourpassword")
profile = linkedin.get_profile("billy-g")

print(profile)

Get only particular item

from linkedin_api import Linkedin

linkedin = Linkedin("youremail", "yourpassword")
profile = linkedin.get_profile("billy-g")

print(profile["summary"])
print(profile["firstName"])

Get more user linkedin data and import to csv

import csv
from linkedin_api import Linkedin

# field header for csv
field_names = ['No', 'Name', 'Email', 'Contact','Address']

dataUsers = []

# users linkedin
# add your linkedin user that want you scrape here
usersLinkedin = ["aulina-indah","muhammad-ichsanul-fadhil"]

# increment number
no = 0

# do scrape
linkedin = Linkedin("ich***l67@gmail.com", "***")

for user in usersLinkedin:
    no += 1

    profile = linkedin.get_profile(user)
    profileContact = linkedin.get_profile_contact_info(user)

    userTemp = {
        'No': no,
        'Name': profile['firstName'] + ' ' + profile['lastName'],
        'Email': profileContact['email_address'],
        'Contact' : profileContact['phone_numbers'][0]['number']
        'Address' : profile['geoLocationName']
    }

    dataUsers.append(userTemp)

with open('linkedin.csv', 'w', newline='') as csvfile:
    writer = csv.DictWriter(csvfile, fieldnames = field_names)
    writer.writeheader()
    writer.writerows(dataUsers)

and more.....

You can find any more api at https://linkedin-api.readthedocs.io/en/latest/api.html

Thank you 😉