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Richard Reis
Richard Reis

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How to think like a programmer — lessons in problem solving

This post originally appeared on Medium

If you’re interested in programming, you may well have seen this quote before:

“Everyone in this country should learn to program a computer, because it teaches you to think.” — Steve Jobs

You probably also wondered what does it mean, exactly, to think like a programmer? And how do you do it??

Essentially, it’s all about a more effective way for problem solving.

In this post, my goal is to teach you that way.

By the end of it, you’ll know exactly what steps to take to be a better problem-solver.

Why is this important?

Problem solving is the meta-skill.

We all have problems. Big and small. How we deal with them is sometimes, well…pretty random.

Unless you have a system, this is probably how you “solve” problems (which is what I did when I started coding):

  1. Try a solution.
  2. If that doesn’t work, try another one.
  3. If that doesn’t work, repeat step 2 until you luck out.

Look, sometimes you luck out. But that is the worst way to solve problems! And it’s a huge, huge waste of time.

The best way involves a) having a framework and b) practicing it.

“Almost all employers prioritize problem-solving skills first.
Problem-solving skills are almost unanimously the most important qualification that employers look for….more than programming languages proficiency, debugging, and system design.
Demonstrating computational thinking or the ability to break down large, complex problems is just as valuable (if not more so) than the baseline technical skills required for a job.” — Hacker Rank (2018 Developer Skills Report)

Have a framework

To find the right framework, I followed the advice in Tim Ferriss’ book on learning, “The 4-Hour Chef”.

It led me to interview two really impressive people: C. Jordan Ball (ranked 1st or 2nd out of 65,000+ users on Coderbyte), and V. Anton Spraul (author of the book “Think Like a Programmer: An Introduction to Creative Problem Solving”).

I asked them the same questions, and guess what? Their answers were pretty similar!

Soon, you too will know them.

Sidenote: this doesn’t mean they did everything the same way. Everyone is different. You’ll be different. But if you start with principles we all agree are good, you’ll get a lot further a lot quicker.

“The biggest mistake I see new programmers make is focusing on learning syntax instead of learning how to solve problems.” — V. Anton Spraul

So, what should you do when you encounter a new problem?

Here are the steps:

1. Understand

Know exactly what is being asked. Most hard problems are hard because you don’t understand them (hence why this is the first step).

How to know when you understand a problem? When you can explain it in plain English.

Do you remember being stuck on a problem, you start explaining it, and you instantly see holes in the logic you didn’t see before?

Most programmers know this feeling.

This is why you should write down your problem, doodle a diagram, or tell someone else about it (or thing… some people use a rubber duck).

“If you can’t explain something in simple terms, you don’t understand it.” — Richard Feynman

2. Plan

Don’t dive right into solving without a plan (and somehow hope you can muddle your way through). Plan your solution!

Nothing can help you if you can’t write down the exact steps.

In programming, this means don’t start hacking straight away. Give your brain time to analyze the problem and process the information.

To get a good plan, answer this question:

“Given input X, what are the steps necessary to return output Y?”

Sidenote: Programmers have a great tool to help them with this… Comments!

3. Divide

Pay attention. This is the most important step of all.

Do not try to solve one big problem. You will cry.

Instead, break it into sub-problems. These sub-problems are much easier to solve.

Then, solve each sub-problem one by one. Begin with the simplest. Simplest means you know the answer (or are closer to that answer).

After that, simplest means this sub-problem being solved doesn’t depend on others being solved.

Once you solved every sub-problem, connect the dots.

Connecting all your “sub-solutions” will give you the solution to the original problem. Congratulations!

This technique is a cornerstone of problem-solving. Remember it (read this step again, if you must).

“If I could teach every beginning programmer one problem-solving skill, it would be the ‘reduce the problem technique.’
For example, suppose you’re a new programmer and you’re asked to write a program that reads ten numbers and figures out which number is the third highest. For a brand-new programmer, that can be a tough assignment, even though it only requires basic programming syntax.
If you’re stuck, you should reduce the problem to something simpler. Instead of the third-highest number, what about finding the highest overall? Still too tough? What about finding the largest of just three numbers? Or the larger of two?
Reduce the problem to the point where you know how to solve it and write the solution. Then expand the problem slightly and rewrite the solution to match, and keep going until you are back where you started.” — V. Anton Spraul

4. Stuck?

By now, you’re probably sitting there thinking “Hey Richard... That’s cool and all, but what if I’m stuck and can’t even solve a sub-problem??”

First off, take a deep breath. Second, that’s fair.

Don’t worry though, friend. This happens to everyone!

The difference is the best programmers/problem-solvers are more curious about bugs/errors than irritated.

In fact, here are three things to try when facing a whammy:

  • Debug: Go step by step through your solution trying to find where you went wrong. Programmers call this debugging (in fact, this is all a debugger does).

“The art of debugging is figuring out what you really told your program to do rather than what you thought you told it to do.”” — Andrew Singer

  • Reassess: Take a step back. Look at the problem from another perspective. Is there anything that can be abstracted to a more general approach?

“Sometimes we get so lost in the details of a problem that we overlook general principles that would solve the problem at a more general level. […]
The classic example of this, of course, is the summation of a long list of consecutive integers, 1 + 2 + 3 + … + n, which a very young Gauss quickly recognized was simply n(n+1)/2, thus avoiding the effort of having to do the addition.” — C. Jordan Ball

Sidenote: Another way of reassessing is starting anew. Delete everything and begin again with fresh eyes. I’m serious. You’ll be dumbfounded at how effective this is.

  • Research: Ahh, good ol’ Google. You read that right. No matter what problem you have, someone has probably solved it. Find that person/ solution. In fact, do this even if you solved the problem! (You can learn a lot from other people’s solutions).

Caveat: Don’t look for a solution to the big problem. Only look for solutions to sub-problems. Why? Because unless you struggle (even a little bit), you won’t learn anything. If you don’t learn anything, you wasted your time.

Practice

Don’t expect to be great after just one week. If you want to be a good problem-solver, solve a lot of problems!

Practice. Practice. Practice. It’ll only be a matter of time before you recognize that “this problem could easily be solved with .”

How to practice? There are options out the wazoo!

Chess puzzles, math problems, Sudoku, Go, Monopoly, video-games, cryptokitties, bla… bla… bla….

In fact, a common pattern amongst successful people is their habit of practicing “micro problem-solving.” For example, Peter Thiel plays chess, and Elon Musk plays video-games.

“Byron Reeves said ‘If you want to see what business leadership may look like in three to five years, look at what’s happening in online games.’
Fast-forward to today. Elon [Musk], Reid [Hoffman], Mark Zuckerberg and many others say that games have been foundational to their success in building their companies.” — Mary Meeker (2017 internet trends report)

Does this mean you should just play video-games? Not at all.

But what are video-games all about? That’s right, problem-solving!

So, what you should do is find an outlet to practice. Something that allows you to solve many micro-problems (ideally, something you enjoy).

For example, I enjoy coding challenges. Every day, I try to solve at least one challenge (usually on Coderbyte).

Like I said, all problems share similar patterns.

Conclusion

That’s all folks!

Now, you know better what it means to “think like a programmer.”

You also know that problem-solving is an incredible skill to cultivate (the meta-skill).

As if that wasn’t enough, notice how you also know what to do to practice your problem-solving skills!

Phew… Pretty cool right?

Finally, I wish you encounter many problems.

You read that right. At least now you know how to solve them! (also, you’ll learn that with every solution, you improve).

“Just when you think you’ve successfully navigated one obstacle, another emerges. But that’s what keeps life interesting.[…]
Life is a process of breaking through these impediments — a series of fortified lines that we must break through.
Each time, you’ll learn something.
Each time, you’ll develop strength, wisdom, and perspective.
Each time, a little more of the competition falls away. Until all that is left is you: the best version of you.” — Ryan Holiday (The Obstacle is the Way)

Now, go solve some problems!

And best of luck 🙂

Special thanks to C. Jordan Ball and V. Anton Spraul. All the good advice here came from them.

Also, all the programming knowledge I’ve acquired in such a short time wouldn’t have happened without Lambda School. Can’t thank/ recommend them enough.

Thanks for reading! 😊

Top comments (6)

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joshcheek profile image
Josh Cheek • Edited

Trying things that might work is a reasonable strategy in many situations. Not every problem merits contemplation. Eg you're in a new language and you need the sum of the numbers, I'd advocate you just try typing num1 + num2, b/c lets be honest, it's probably that. Maybe you gotta guess at how to tweak it for some new language (+ num1 num2), but same thing. Predicting and verifying are more effective than many docs and blogs. But yeah, there are times when it's better to understand how things work: if you guess wrong several times in a row, or if you can't find a way to cheaply try out the possibilities, or if you get it right, but don't understand why.

Also, it's a mistake to require understanding before beginning. In part, it means you can never do something unless you understand it. Many problems do not have this attribute. Eg "what should the product be?" For many domains, you cannot know the answer until you start working on the problem (or you hit "analysis paralysis"), the feedback cycle is incredibly important.

Also, the described approach requires you to invest in understanding and then planning before you begin. But not all things are worth investing in. It's hugely advantageous to be able to start something you don't understand, to drive in a direction that you know is progress, even if you can't see how it gets you to the solution that you aren't sure what it is. Not saying you should do that for every problem, just that it's the right approach to many types of problems.

Number 3 is legit. Breaking a problem out of its complex context and solving it in isolation is the best way to understand, usually the path of least resistance (though figuring out how to break it out can be difficult, depending on the domain), and it's the quickest way to get feedback on an idea.

Another useful thing to do when stuck is to confirm your premises. Eg if the thing isn't making sense, maybe it's because your understanding is wrong, so you need to question and verify those things.

And another useful thing to do when you get stuck is to approach the problem from the opposite end. Eg if you're building up from the bottom (composing new functionality out of existing functionality), then try switching to the top (writing what you ultimately want, even though the things you're using don't exist yet), and vice versa. Sometimes you have to switch back and forth multiple times before you finally see how / where they connect.

Another good way to practice is to re-solve problems you previously solved. It probably takes me three to 5 times, re-solving a really difficult problem, before I feel like I've gotten 80% of the insights it had to offer. What's especially nice about this is that it gets easier with each iteration. So the cost of re-solving goes down, but the value stays high for quite a while.

Anyway, nice post. Despite being numbered, the list is best traversed nonlinearly.

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jibinp profile image
Jibin Philipose

I think I saw this in medium by freecodecamp it was a good article.

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richardreeze profile image
Richard Reis

Thank you!

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richardreeze profile image
Richard Reis

Musk tweets about what games he's playing every now and then lol.
Business Insider published a list here: businessinsider.com/elon-musk-favo...

As for Thiel, his game is chess. According to ChessBase, Thiel "was a US-rated Chess Master and one of the highest ranked under-21 players in the country."
This GQ article talks a bit more about it: gq.com/story/its-all-a-game-to-pet...

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uchetweets profile image
Uchenna Nwosu

This was epic and really enlightening. Thanks a lot Richard.

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richardreeze profile image
Richard Reis

Thank you for the kind words, Uchenna :)