Project Euler Template

ATTENTION !!

NEVER UPLOAD CODE SOLUTIONS TO A PUBLIC REPOSITORY!!

Project Euler consists of challenges

Do not upload answers

You don't want to be that guy to ruin such a nice project, do you?

DISCLAIMER

From the webpage: https://projecteuler.net/about

The popularity of Project Euler has increased tremendously over the years since its inception through the concerted effort of numerous people.

Members have generally taken pride in showing their achievements. The obvious place to do so is the forum that is set up for each problem. However the increasing popularity has also been attracting people with a different agenda. With so many internet sites publishing answers for the PE problems instead of using the forum on this site, some people now seem to take pride in gathering and submitting those answers for whatever reason.

It is humanly impossible for Project Euler, or indeed any member, to reliably differentiate those people from members that have solved the problems under their own steam. The ranking lists on Project Euler should be interpreted for what they are: an indication of the number of correct answers submitted by the member in question and validated by our answer checker. Individual members themselves know best what they have achieved on their own. Laying too much stress on competition might spoil the fun of problem solving which is one of the purposes of Project Euler. Also, any claim from a member about his own achievement cannot be supported as trustworthy by Project Euler. If critical, other means from third parties would be required to verify such claims.

Providing quality problems for entertainment and educational purposes will continue to be the main goal of Project Euler, regardless of the intentions of a minority of the members.

Files

• peN.c : template to start your solution
• projecteuler.h : a library to set up things easy
• projecteuler.c : functions you collect while learning

Usage

• To create your first exercise using make. Suppose you are programming exercise number 1154. Then do:
  • make pe1154.c

This will copy and correct automatically the name of the exercise to a new file:

pe1154.c

where you will create your master piece to solve problem number 1154!

• What now?

  • Open the file pe1154.c with your preferred editor (vim, of course ;)
  • Don't change anything in function main(). Let it there as it is. Your project starts in the function PEN() bellow main().
  • Immediately before function PEN(), copy and paste as a comment the Project Euler Question Text, that is, the description of the problem you need to solve.
  • Go for it! You can write your code all inside PEN() or create bellow it as many auxiliary functions as you need.

• File projecteuler.c and projecteuler.h:

  • If, while solving one hard problem, you come up with a nice math function that you suppose you will need again soon, don't hesitate to update the library and add your contribution to it. Next exercise you do, you will be able to just use whatever you created before.

Compile

• There is a makefile there to help you. To compile, use:

$ make pe1154.x SRC=projecteuler.c

• If you are into versions, you can set them as:

$ make pe1154.x SRC=projecteuler.c MAJOR=4 MINOR=2

• If scanf() gives you warnings you don't care about (return value ignored for scanf or such), you can easy it by:

$ make pe1154.x SRC=projecteuler.c MAJOR=4 MINOR=2 FORTIFY=0

• There are other options you might want:
  • Turn off DEBUG mode and compile with fast optimizations with: DEBUG=0
  • Define something on your own.
    • If it is an integer, just do: D=SOMETHING=INTEGER
    • If you want a char, then: D="SOMETHING=\'A\'"
  • To see more options, vi makefile and look the variables there.

Keep track

When running, your program will capture CTRL-C to print useful information. You can put anything you want printed inside the variable funcdata[SBUFF]. Just add this command inside some loop and it will update you when you hit CTRL-C:

snprintf(funcdata, SBUFF, "Trying r = %lu\n", r);

One minute rule

• Exercises in Project Euler are carefully created to have a correct answer calculated by a good program under ONE MINUTE!

Sometimes your program takes a bit longer, but keep this rule in mind: if it is taking too long, change your algorithm, change the paradigm, change the way you are thinking the whole thing! There is surely a better, faster way!

Good luck!

Author & License

• This document and templates were created by:
• Prof. Ruben Carlo Benante
• Email. rcb at beco dot cc
• Date: 2017-12-01
• License: GPL v3