Project Euler has lots of challenging problems. No solutions will be posted as I don't want to spoil it for others! Drop me an email if you think I can help you. Solved questions are highlighted in Green and clicking on it will link you to the related post. Those in Amber are in progress. Clicking on unsolved tiles will take you to the question on Project Euler's site!

I decided to create this post because I thought it would be extremely inconvenient to create a new post whenever I finish a few problems. I think I will just lump everything into a gigantic post for 1 to 100, since they are relatively trivial problems. The headers are arranged...

Question 14 Question 15 Question 16 Question 17 14 was simple. Since the Collatz Problem has not been proved yet, I assume that there’s no smart way to do this…? In any case, C is really fast. In case this requires some crazy long loop. Coded it in C and...

Question 11 Question 13 Alright. You must be wondering why I skipped 12. Well there’s an elegant solution to 12, which I haven’t thought of yet. I will get it to soon, and I will most probably just update this post than create a new one. 11 was fairly simple....

Question 541 Harmonic Number Stirling Numbers Wolstenholme's Theorem Part 1 I started this problem exactly 7 days ago, on 3rd January 2016. It seemed like a really challenging problem, as they rate at which it was being solved was not rising fast. Take Problem 542 for example, at the time...

Question 358 Cyclic Number Full Reptend Prime Part 1 This question seems relatively simple. It’s simply finding a full reptend prime. You can check out the definition in the link. To determine if a number is a reptend prime, it has to be a primitive root modulo n, which in...

Question 351 Euler's Totient Function This is a back post as well. I finished 351 before starting this website. 351 has a difficulty of 25%, so I guess I will talk about it. The first part of the problem is to figure out what mathematical equation actually models such a...

Question 1 Question 2 Question 3 Question 4 Question 5 Question 6 Alright. I did question 1 to 6 before starting this website. As such, I didn’t post about it. However, the questions are relatively simple so I won’t be talking about it. This is more of a cursory post...

Question 100 Diophantine Equation Pell's Equation I decided to skip the first few questions as it’s just tedious implementation. I jumped to 100 and thought it was interesting, so why not? It turned out to be a pretty tough problem for me because I haven’t seen such problems before. My...

Question 9 Question 10 9 was a relatively interesting question on pythagorean triplets. An example of a pythogorean triplet would be 3^2 + 4^2 = 5^2. There are actually many more. Turns out that we can use Euclid’s formula to find out the variables a, b and c. These variables...

Question 7 Question 8 Just finished question 7 and 8. Relatively easy questions that could be done very quickly in python. However, I decided to do these questions in C as I would like to become better at C. 7 was pretty much very straight forward as it was just...