Forem: Jose Ross Barredo

Prepping for DSAs: Make Array Consecutive

Jose Ross Barredo — Mon, 09 Mar 2020 02:16:58 +0000

PROBLEM

BRUTE FORCE

While I was thinking of a brute force algorithm, one idea that came into my mind was:

Having that algorithm in mind, I wanted to check the efficiency of my algorithm. I can implement my own Quicksort algorithm, however for this problem, I intend to practice the DRY principle. Sorting an array in Java (line 1) is guaranteed to be O(n log n). The next iteration starting on line 2 would take O(n) since we are iterating each element in the array. I believe the other lines are constant. As a whole, the running time of our brute force algorithm is O(n log n) since we only care about the dominant term from O( n + n log n).

The question now is, "Is this enough?" At this rate, there is no other way that I know of that can lessen the running time. The "best" sorting algorithm suitable for this problem is of O(n log n).

I can make it more concise.

Final Solution

How did I arrive here?

Motivation: We can count the length of the range between two numbers x,y where x is the minimum and y is the maximum. With out array sorted out in increasing order:

statues[statues.length - 1] is the maximum element which happens to be the last element of the array since it is sorted in increasing order. Since arrays are zero-indexed, hence comes the minus 1 from the total length. statues[0] is the minimum element. The difference of max and min is the length of the range between those numbers.

We added 1 to the difference of max and min since, again, arrays are zero-indexed. ((statues[statues.length - 1] - statues[0]) + 1) indicates the supposed length of the range given the min and max.

The - statues.length at the end of the formula is how we get the missing numbers in our range to satisfy the requirement of getting the missing numbers of elements in our array which the element should be exactly 1 greater that its previous(keep in mind that this is sorted in increasing order).

The running time of this algorithm is still O(n log n).

To illustrate:

PS: I would appreciate comments in improving the algorithm that I have.

Prepping for Data Structures and Algorithm

Jose Ross Barredo — Mon, 09 Mar 2020 02:13:52 +0000

I have always thought of Technical Interviews especially during Data Structures and Algorithm questions to be detrimental. I always find it hard to wrap around the questions and find a good algorithm for it. I coward and tend to expect the worse. Until one day, I told myself to courage up!

As a software engineer, coder, developer, software developer or whatever you call yourself, having the foundation on data structures and algorithms (DSA) is a must on our tool belt. Having that foundation is fundamental to help shape our critical minds into reaching a solution to problems which is both efficient and effective. For interviewers, it gives them a peek to what our perspective is when facing obstacles in coding.

Not acing that interview is your fault alone. The best way to prevent it is to prepare and practice, then prepare and practice again. It is recursive.

Preparing for technical interviews is very subjective. As for me, I am making this article as an introduction to one of my preparation techniques.

I will be posting my train of thoughts as to how I would solve a DSA problem. Think of it as a mock interview but a monologue written. Disclaimer, I am in no way expert and I am still learning. I would love to receive feedback and comments that would help me.

The problems that I will be solving are questions from various coding platforms online.

This is me prepping for my technical interview.

Question: How was the assumption made?

Jose Ross Barredo — Thu, 20 Feb 2020 02:21:18 +0000

Hi guys! I have been reading "Cracking the Coding Interview 6th Edition".. On Chapter 0 - Big O, I have problem understanding an assumption made to a problem on Example 3.

void printUnorderedPairs(int[] array){
  for(int i = 0; i < array.length; i++){
    for(int j = i + 1; j < array.length; j++){
      ...
    }
  }
}

Under What It Means section, it assumed that:

There are N^2 total pairs. Roughly half of those will have i < j and the remaining half will have i > j. This code goes through roughly n^2/2 pairs so it does O(N^2) work.

My question is, how was the assumption made on Roughly half of those will have i < j and the remaining half will have i > j done? Can someone explain it to me please?

Thanks!

BASHing through the terminal

Jose Ross Barredo — Mon, 15 Apr 2019 14:34:34 +0000

My fascination with Bash Shell Scripting started just 3 months ago. Prior to that, I never had any knowledge with what and how to bash. It has proven to be a powerful tool to help you automate basic routine tasks.

My first encounter with bash was when my lead developer told me to create a simple cronjob to execute a SQL script to import into the database. With limitations from the SQL like variable value replacement from a random source, SQL just couldn't do the job. That is when I "discovered" bash shell scripting. From then on, my journey with bashing through the terminal started.

As a UNIX Linux user, I do basic shell commands like ls, sudo or cd. I know just the ordinary commands from my bachelors but never have I thought you could do all sorts of basic algorithm constructs just like how a programming language would from handling files, array declaration, string replacement and down to looping, conditional statements and the like.

Learning to Bash, by bash I mean shell scripting, is intimidating but it is actually easy than it looks. Though, I must say developers with limited programming background might not be for bash. Learning Bash has a shallow learning curve.

Shell scripting allows us to extensively use the shell's abilities and automate a lot of tasks that would otherwise require long and complicated commands. It really does save time when you automate routine tasks like monthly backup compression or SQL import.

This article is the first part to my Bash tutorial posts. I hope you will not only enjoy but also will learn a thing or two from my Bash Shell Scripting tutorials soon.

But before you go, have you used Bash Shell Scripting yourself?

Day 1: Booting Up My React.js

Jose Ross Barredo — Sat, 05 Jan 2019 14:46:45 +0000

"The key to being a successful programmer is to learn how to learn."
- Shannon Burns

As technologies get updated everyday and as new technologies emerge, as curious as we are of a developer, we couldn't help but get intrigued by what these stuff have to offer. Everything seems so fast that you get swallowed by tons of great new technologies while you're at it. The virtual world is a fast-paced place to be in.

If you were able to read the first part of my series on my journey on the #301DaysOfCode,

Day 0: Planning Phase

Jose Ross Barredo ・ Jan 4 '19 ・ 1 min read

#301daysofcode #career #beginners

I spent the first day figuring out the path Im taking as a developer to work and hone on. I spent hours thinking what my strengths and weaknesses are as a software developer. I listed down my skills and rated them honestly. After 2 grueling hours, I still was not able to figure things out.

Feeling defeated, I opened my Youtube and the first video that popped out was freeCodeCamp's Learn React.js - Full Course for Beginners Tutorial.

It was a great way to start my #301DaysofCode. As of this writing, I am about to finish the video tutorial and will definitely post my thoughts on what I learned. In addition, with every readings that I go through, I will be developing a mini capstone for each one.

If you have any links of where I could get some great tutorials for React.js, please do so comment down below. I'm also asking for your suggestions what I could develop using React.js as a beginner's project.

Day 0: Planning Phase

Jose Ross Barredo — Fri, 04 Jan 2019 05:45:00 +0000

2019 - new year, new goals.

Today, I am fully commiting myself to the #301DaysofCode to be competent enough and be a more awesome software developer. No more pro·cras·ti·na·tion, no more slacking, and definitely no more to sleeping for more than 10 hours a day.

With full of enthusiasm, this year will be completely different as i have setup goals that I want to achieve before 2020 comes. As a developer for 4+ years, I feel like a grinch slouching off just waiting for things to happen. But No! Ain't nobody got time for that! I will be more proactive this time and will be definitely make things happen.

My ultimate goal ever since starting in this industry is to be employed by one of those companies aligned in SILICON VALLEY (you know what I meant). It will be a difficult task but nothing is difficult when you start from ground 0 till N-1. Being said, Ill work with opensource projects and start on making personal projects.

This is Day 0 of my #301DaysofCode. As I brainstorm what path will I go to while on this journey, I will be documenting every steps I take, every hurdles I face and every solutions I did. This is really exciting and I am very eager to start. I hope you stick on with me and be a part of this wonderful new journey of mine. Your support will really help me a lot.

Establish Self as a Software Developer: Help!!

Jose Ross Barredo — Wed, 02 Jan 2019 13:39:10 +0000

Dear software developer gods, I seek your advice. I seek your mentorship. What must I do?

I am not new to software development. In fact, I have been in this industry for almost 5 years now but I never see myself as a competent and a talented developer. I lack a profile visibility as a software developer.

I have been watching tons of tutorials online and followed most of them locally. From front-end to backend to being a full-stack. However, I never haven't "been there" or received the pinnacle of my career.

This year I am aiming to help in open source and have a lot of onlinve visibility but I don't know where to start.

I need direction. I need a professional help. I don't want to be a mediocre developer. I wanna improve and learn more but I don't know where to go next.

Dear software developer gods, I seek your advice. I seek your mentorship. What must I do?

Explain git pull --rebase to me like Im five

Jose Ross Barredo — Fri, 29 Sep 2017 14:49:57 +0000

I have been using git for years now and honestly, I really don't quite understand how certain codes work like for in this case git pull --rebase. Can someone explain to me how rebase works like I'm five?

Thanks and you're awesome!

Journey to Artificial Intelligence

Jose Ross Barredo — Wed, 27 Sep 2017 12:14:00 +0000

One might say that it is pretty intimidating to get yourself into learning Artificial Intelligence. Well, actually it is. AI is such an advanced and a diverse stream of knowledge that once you encounter the word itself, you get drowned with anxietal thoughts.

The possibilty of being able to grasp the know-hows of artificial intelligence was artificial for me. I never considered crossing the path towards learning it. Imagine the algorithms, math and science that you need to immerse yourself with. It seems to me that it would take a miracle before I would even dare start with it. It is just too highly technical and is just out of the bounds of my knowledge.

I was overthinking. Anxiety and fear took over me. Learning new stuff can really be intimidating especially if you dont know an inch about the topic. I then realize that if I continue to let my insecurities prevail, how can I succeed as a better programmer and as a better computer scientist?

Eventually, I got motived when I enrolled myself in a Masters in Computer Science. The possibilities of where you might arrive when learning AI is exponential. I got interested even more after I started reading Peter Norvig's and Stuart J. Russell's book on Artificial Intelligence: A Modern Approach. Since then I could not stop myself from learning. I am literally deep diving myself into it.

As my knowledge on Artificial Knowledge progress, I would then like to share with you with what I might be able to explain and teach. I will be posting a series of topics about AI. Let us learn together and venture the world of AI.

This is my journey with Artificial Intelligence and it has just begun. I am eager and excited for this journey!