Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • World
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (No Skin)
  • No Skin
Collapse
Code Project
  1. Home
  2. The Lounge
  3. Coding Challenge Of The Day

Coding Challenge Of The Day

Scheduled Pinned Locked Moved The Lounge
c++architecture
51 Posts 30 Posters 0 Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • C Chris Maunder

    Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

    cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

    W Offline
    W Offline
    wizardzz
    wrote on last edited by
    #12

    I never enter a contest without knowing the prize, for tax purposes, but also in this case, it could be a job at CP... :doh:

    C 1 Reply Last reply
    0
    • C Chris Maunder

      You get points for at least writing code. As opposed to some members... (dark looks all 'round).

      cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

      W Offline
      W Offline
      wizardzz
      wrote on last edited by
      #13

      I didn't see you award him any points. Go on, 5 him!

      S S 2 Replies Last reply
      0
      • W wizardzz

        I never enter a contest without knowing the prize, for tax purposes, but also in this case, it could be a job at CP... :doh:

        C Offline
        C Offline
        Chris Maunder
        wrote on last edited by
        #14

        Actually it's a personality test to see who among you are worthy of being labelled a Brogrammer.

        cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

        B 1 Reply Last reply
        0
        • W wizardzz

          I didn't see you award him any points. Go on, 5 him!

          S Offline
          S Offline
          S Houghtelin
          wrote on last edited by
          #15

          Thanks wizardzz, I suppose he meant like virtual points, or maybe pints, I'll definitely takes pints! :-D

          It was broke, so I fixed it.

          1 Reply Last reply
          0
          • W wizardzz

            I didn't see you award him any points. Go on, 5 him!

            S Offline
            S Offline
            Steve Mayfield
            wrote on last edited by
            #16

            Don't you mean 'V' him?

            Steve _________________ I C(++) therefore I am

            A 1 Reply Last reply
            0
            • C Chris Maunder

              Actually it's a personality test to see who among you are worthy of being labelled a Brogrammer.

              cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

              B Offline
              B Offline
              Bassam Abdul Baki
              wrote on last edited by
              #17

              You may want to snag CodeBroject.com just in case (CodePreject.com too).

              Web - BM - RSS - Math - LinkedIn

              1 Reply Last reply
              0
              • C Chris Maunder

                You get points for at least writing code. As opposed to some members... (dark looks all 'round).

                cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                S Offline
                S Offline
                S Houghtelin
                wrote on last edited by
                #18

                Just like positive reenforcment in the schools today, everybody gets a trophy, even when they're wrong. Thanks! :thumbsup: :-D

                It was broke, so I fixed it.

                1 Reply Last reply
                0
                • C Chris Maunder

                  Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

                  cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                  S Offline
                  S Offline
                  Sentenryu
                  wrote on last edited by
                  #19

                  as a nerd, i can't resist... between, it's only a quick n' dirty solution:

                  public static int RomanToArabic(string romans) {
                  if (string.IsNullOrWhiteSpace(romans))
                  {
                  return 0;
                  }
                  //remove whitespace...
                  romans = romans.Replace(" ", string.Empty);
                  //make sure no one pass out an "A" for example...
                  if (!Regex.IsMatch(romans, "(I|V|X|C|M|D|L)+"))
                  {
                  throw new ArgumentException("Invalid numeral!!");
                  }

                          //actual validation that matters (based on http://en.wikipedia.org/wiki/Roman\_numerals): 
                          //The symbols "I", "X", "C", and "M" can be repeated three times in succession, but no more. "D", "L", and "V" can never be repeated.
                          string invalidSequences = "(XXXX+)|(IIII+)|(CCCC+)|(MMMM+)|(DD+)|(LL+)|(VV+)";
                  
                          if (Regex.IsMatch(romans, invalidSequences))
                          {
                              throw new ArgumentException("Invalid sequence!!");
                          }
                  
                          int result = 0;
                  
                          result += Regex.Matches(romans, "IV").Count \* 4;
                          romans = Regex.Replace(romans, "IV", string.Empty);
                  
                          result += Regex.Matches(romans, "IX").Count \* 9;
                          romans = Regex.Replace(romans, "IX", string.Empty);
                  
                          result += Regex.Matches(romans, "XL").Count \* 40;
                          romans = Regex.Replace(romans, "XL", string.Empty);
                  
                          result += Regex.Matches(romans, "XC").Count \* 90;
                          romans = Regex.Replace(romans, "XC", string.Empty);
                  
                          result += Regex.Matches(romans, "CD").Count \* 400;
                          romans = Regex.Replace(romans, "CD", string.Empty);
                  
                          result += Regex.Matches(romans, "CM").Count \* 900;
                          romans = Regex.Replace(romans, "CM", string.Empty);
                  
                          result += romans.Count(x => x == 'I');
                          romans = romans.Replace("I", string.Empty);
                  
                          result += romans.Count(x => x == 'V') \* 5;
                          romans = romans.Replace("V", string.Empty);
                  
                          result += romans.Count(x => x == 'X') \* 10;
                          romans = romans.Replace("X", string.Empty);
                  
                          result += romans.Count(x => x == 'L') \* 50;
                          romans = romans.Replace("L", string.Empty);
                  
                          result += romans.Count(x => x == 'C') \* 100;
                          romans = romans.Replace("C", string.Empty);
                  
                          result += romans.Count(x => x == 'D') \* 500;
                          romans = romans.Replace("D", strin
                  
                  1 Reply Last reply
                  0
                  • S Steve Mayfield

                    Don't you mean 'V' him?

                    Steve _________________ I C(++) therefore I am

                    A Offline
                    A Offline
                    AspDotNetDev
                    wrote on last edited by
                    #20

                    Good catch. Live long and prosper.

                    Thou mewling ill-breeding pignut!

                    1 Reply Last reply
                    0
                    • C Chris Maunder

                      Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

                      cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                      K Offline
                      K Offline
                      Karl Sanford
                      wrote on last edited by
                      #21

                      Chris Maunder wrote:

                      Roman numerals to Arabic numbers

                      totally read this backward... at least now I have a solution for Arabic to Roman Numerals :doh:

                      Be The Noise

                      1 Reply Last reply
                      0
                      • C Chris Maunder

                        Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

                        cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                        L Offline
                        L Offline
                        Lost User
                        wrote on last edited by
                        #22

                        #!/usr/bin/python

                        import sys

                        I=1
                        V=5
                        X=10
                        L=50
                        C=100
                        D=500
                        M=1000

                        a=0
                        b=0
                        c=0

                        for d in map(eval,sys.argv[1]):
                        if d > a:
                        b += d - c
                        c = 0
                        else:
                        b += c
                        c = d
                        a = d
                        print b + c

                        L 1 Reply Last reply
                        0
                        • J Joan M

                          Chris... you should know that we don't make homework here... :rolleyes:

                          [www.tamautomation.com] Robots, CNC and PLC machines for grinding and polishing.

                          C Offline
                          C Offline
                          Corporal Agarn
                          wrote on last edited by
                          #23

                          Tried to leave a similar message earlier but CP locked. I was going to add this is not QA. :)

                          1 Reply Last reply
                          0
                          • C Chris Maunder

                            Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

                            cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                            J Offline
                            J Offline
                            jesarg
                            wrote on last edited by
                            #24

                            private int ToInt(string rom)
                            {
                            int length = rom.Length;
                            int result = 0;
                            for(int loop1=0; loop1 < length; loop1++)
                            {
                            char current = rom[loop1];
                            char next = loop1 < length - 1 ? rom[loop1 + 1] : ' ';
                            switch(current)
                            {
                            case 'I':
                            result += next == 'V' || next == 'X' ? -1 : 1;
                            break;
                            case 'V':
                            result += 5;
                            break;
                            case 'X':
                            result += next == 'L' || next == 'C' ? -10 : 10;
                            break;
                            case 'L':
                            result += 50;
                            break;
                            case 'C':
                            result += next == 'D' || next == 'M' ? -100 : 100;
                            break;
                            case 'D':
                            result += 500;
                            break;
                            case 'M':
                            result += 1000;
                            break;
                            }
                            }
                            return result;
                            }

                            1 Reply Last reply
                            0
                            • L Lost User

                              #!/usr/bin/python

                              import sys

                              I=1
                              V=5
                              X=10
                              L=50
                              C=100
                              D=500
                              M=1000

                              a=0
                              b=0
                              c=0

                              for d in map(eval,sys.argv[1]):
                              if d > a:
                              b += d - c
                              c = 0
                              else:
                              b += c
                              c = d
                              a = d
                              print b + c

                              L Offline
                              L Offline
                              Lost User
                              wrote on last edited by
                              #25

                              Or, somewhat more tersely,

                              def r2d3(r,(s,M,C,X,I,z,V,L,D)=["%%s%d"%v for v in[1001,1000,100,10,1,0,5,50,500]]):
                              return eval("".join([
                              p%"+-"[eval( p%"%s>"%d%"")]
                              for d,p in zip(map(eval,'%sz'%r),map(eval,'s%s'%r))
                              ][1:]))

                              Y 1 Reply Last reply
                              0
                              • C Chris Meech

                                I once met a well formed roman, when I was touring through Italy. :cool:

                                Chris Meech I am Canadian. [heard in a local bar] In theory there is no difference between theory and practice. In practice there is. [Yogi Berra] posting about Crystal Reports here is like discussing gay marriage on a catholic church’s website.[Nishant Sivakumar]

                                L Offline
                                L Offline
                                Luc Pattyn
                                wrote on last edited by
                                #26

                                that would be where most Romans are, don't you think? :)

                                Luc Pattyn [My Articles] Nil Volentibus Arduum

                                1 Reply Last reply
                                0
                                • C Chris Maunder

                                  Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

                                  cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                                  L Offline
                                  L Offline
                                  Luc Pattyn
                                  wrote on last edited by
                                  #27

                                  no arrays, no dictionaries, no obscure language, just some original coding:

                                  public static bool TryParseRoman(string wellFormedRoman, out int val) {
                                  val=0;
                                  int prevDigit=0;
                                  foreach (char c in wellFormedRoman) {
                                  int index="IVXLCDM".IndexOf(c);
                                  if (index<0) {val=0; return false;}
                                  int digit=1;
                                  int factor=5;
                                  while (--index>=0) { digit*=factor; factor=7-factor; }
                                  if (prevDigit

                                  BTW: is it Friday already?

                                  :)

                                  Luc Pattyn [My Articles] Nil Volentibus Arduum

                                  P 1 Reply Last reply
                                  0
                                  • C Chris Maunder

                                    Write a function to convert Roman numerals to Arabic numbers. The smaller the better. Bonus points, as always, for obscure languages and obfuscated assembler.

                                    cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP

                                    P Offline
                                    P Offline
                                    PIEBALDconsult
                                    wrote on last edited by
                                    #28

                                    I'm unsure when I wrote this, but it must have been the 90s, in VAX C or DEC C. I'm shocked (shocked! I say) at the inconsistent braces. :wtf:

                                    size_t
                                    roman2dec
                                    (
                                    char *subject
                                    )
                                    {
                                    size_t result = 0 , current , high = 0 ;
                                    int index ;

                                    for ( index = strlen(subject)-1 ; index >= 0 ; index-- ) {
                                        switch ( (char) \*(subject + index) )
                                        {
                                            case 'I' :
                                            case 'i' : current =    1 ; break ;
                                    
                                            case 'V' :
                                            case 'v' : current =    5 ; break ;
                                    
                                            case 'X' :
                                            case 'x' : current =   10 ; break ;
                                    
                                            case 'L' :
                                            case 'l' : current =   50 ; break ;
                                    
                                            case 'C' :
                                            case 'c' : current =  100 ; break ;
                                    
                                            case 'D' :
                                            case 'd' : current =  500 ; break ;
                                    
                                            case 'M' :
                                            case 'm' : current = 1000 ; break ;
                                    
                                            default  : current =    0 ; break ;
                                        }
                                    
                                        if ( current < high )
                                            result -= current ;
                                        else
                                        {
                                           result += current ;
                                           high = current ;
                                        }
                                    }
                                    
                                    return ( result ) ;
                                    

                                    }

                                    1 Reply Last reply
                                    0
                                    • R Ravi Bhavnani

                                      Spoiler[^] /ravi

                                      My new year resolution: 2048 x 1536 Home | Articles | My .NET bits | Freeware ravib(at)ravib(dot)com

                                      P Offline
                                      P Offline
                                      PIEBALDconsult
                                      wrote on last edited by
                                      #29

                                      That's dreadful. :wtf:

                                      1 Reply Last reply
                                      0
                                      • C Chris Losinger

                                        for well-formed roman numerals, modern rules:

                                        int r2d2(const char *r)
                                        {
                                        int val[128];
                                        memset(val,0,sizeof(int)*128);
                                        val['I']=1; val['V']=5;
                                        val['X']=10; val['L']=50;
                                        val['C']=100; val['D']=500; val['M']=1000;

                                        int a = 0;
                                        for (int cv, pv = 0, i=strlen(r)-1;i>=0;i--)
                                        {
                                        cv = val[r[i]];
                                        a += cv * (pv > cv ? -1 : 1);
                                        pv = cv;
                                        }

                                        return a;
                                        

                                        }

                                        image processing toolkits | batch image processing

                                        P Offline
                                        P Offline
                                        PIEBALDconsult
                                        wrote on last edited by
                                        #30

                                        Seems a waste of RAM.

                                        1 Reply Last reply
                                        0
                                        • C Chris Meech

                                          I once met a well formed roman, when I was touring through Italy. :cool:

                                          Chris Meech I am Canadian. [heard in a local bar] In theory there is no difference between theory and practice. In practice there is. [Yogi Berra] posting about Crystal Reports here is like discussing gay marriage on a catholic church’s website.[Nishant Sivakumar]

                                          A Offline
                                          A Offline
                                          arcosupportus
                                          wrote on last edited by
                                          #31

                                          did you get here number?

                                          1 Reply Last reply
                                          0
                                          Reply
                                          • Reply as topic
                                          Log in to reply
                                          • Oldest to Newest
                                          • Newest to Oldest
                                          • Most Votes


                                          • Login

                                          • Don't have an account? Register

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • World
                                          • Users
                                          • Groups