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ioccc-src
winner
HTML2021–2026
ioccc-src / winner

winner

Winners of the International Obfuscated C Code Contest

Explore on GitHubRead Hacker News discussions
17Distinct people
27Mentions
4Explicit recommenders
1.5KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Winners of the International Obfuscated C Code Contest

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

This one is my favorite: https://github.com/ioccc-src/winner/blob/master/2025/ncw1/pr...

HappMacDonald used a recommendation phrase. 4 indexed comments match. This is a phrase match, not a verdict.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 10:02:05 AM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year27 dated mentions

Observed mentions: 2021-04-02 16:04:27 UTC to 2026-11-01 18:36:41 UTC.

0369122021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments20212022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments20232024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 12 mentions; 0 submissions, 12 comments2026-01-01 00:00:00 UTC to 2027-01-01 00:00:00 UTC (exclusive): 10 mentions; 1 submissions, 9 comments. Incomplete calendar period.2026*

* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC101
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC303
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC101
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC000
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC12012
2026 (partial)2026-01-01 00:00:00 UTC2027-01-01 00:00:00 UTC1019

What Hacker News says

12 sources
tzury·Aug 4, 2025
this one is nice, Wordle shaped Wordle program https://github.com/ioccc-src/winner/blob/master/2024/burton/... #include <stdarg.h> #include <stdlib.h> # include <stdio.h> #define J(J) for (\ _ j=0; j<5; ++j) J; #define/*IOCCC*/I \ \ \ \ _ W,_ O,_ R,_ D,_*L,_*E #define A(A )for(_ j=0; !o&&j<5&&(k = t[l][j]); ++j)A&&++o; typedef/* ; ; */void q; typedef int _ ; typedef char/* */p; struct{ p a [257],b[9][ 5],c[5],d[5 ]; _ e,f; } i;p t[78557 ][5]; _ s,a []={ 9,9,9, 10,13,18,27 ,39,55,1,18 ,2,1,1,35,2 ,19,18,1,52 ,36,35,20,3 ,2,19,18,18 ,69,2,53,1, 52,37,3,20, 36,19,35,18 ,52,86,2,53 ,70,1,69,38 ,4,21,3,37, 19,36,35,25 ,10,+17,15, 26,9,11,12, 23,2,06,18, 13,20,22,14 ,1,24,19,21 ,16,5,7,4,8 ,3},u=' ';_ W(p*a,p*b){ for(p*c=a+5 ;a<c;)*a++= *b++;return 0; } _ O
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(p* a,p b){ p*c =a+5; for(; a<c&&*a-b;) ++a; return a<c?5-(a-c) :0; } _ R(p *a, ... ) { va_list b ; va_start(b, a); vprintf (a,b); exit (1); } q D( p*a){ if (s ==sizeof t/ 5)R("limit" " %d\n",s); p*b=s[t],i, j; for(i=j= 0; i<7&&!j; ++i)if(!(j= *a==10?i:0) )*b++=u|* a ++; j-5||++ s; } q L(p* a,_ b){ for (_ l=0,o=0, k; l<s; o=0 ){ A(i.c[j] &&k-i.c[j]) A(i.a[k])A( i.d[j]&&!O( t[l],i.d[j] ))for(_ f=i .e; f--&&!o ; )A(i.b[f] [j]==k)if(! o){ J(o+=t[ l][j]==a[j] )o=o==5?b!= 5:0; } o?W( t[l],t[--s] ) :++l; } } _ e(I){ for (; O<D; )L[ R++]=E[O+++ D*W];return R; } q S( _ O,_*l){ for (_*s=&a[a[O ]],*e=a[-~O ]+s-a[O]; s <e; ){ _ i= *s++,j=i&15 ,k=l[i>>=4] <l[+j]?k=l[ i],l[i]=l[j ],l[j]=k:i; } } _ o(I){ _ o=0, w=0; for(; o<D&w <D; )L[R++] =E[o+D*W]>= E[w+D*O]?E[ o+++D*W]:E[ w +++ D*O]; return e(O, w,e(W,o,R,D ,L,E),D,L,E ); } q l( _ n,_*f){ for (_* e=f+26, i,j; f<e&&* f>u; f+= i) { for(i=1,j =*f/u; i <n &&f[i]>>5== j; )++i;for (j=0; j <i; ++j)f[j] &= 31,f[j]|=a[ f[j]+a[~-9] ]<<5; S(i,f ); } } q v( _ a,_*w,_*k ){ o(2,3,o( 0,1,0,a,w,k ),a,w,k); o (0,1,0,a+a, k,w); l(a,k ); } p*E(p* d){ _ l,j,k =u,b[u] ,c[ k]; p*e[97] [5 ]={ 0} ; for(l=0; l< k; ++l)c[l] =l; for(l=0 ; l<s; ++l) J(c[t[l][j] -97]+=k)for (l= j=7; j< 22; j+=l)S( l,c+j-l); v (l,b,c);for (l= 0; l<k; ++l)b[c[l]& ~-k]=l; for (k*=3,l= 0; l<s; ++l) { _ i=0; J( i +=b[t[l][j] -97])if(i<k )J(e[i][ j] ||(e[i][j]= t[l],j=4))} for(l=0; l< k; ++l)for( p*b=0,k=j=0 ; j<5&&(b=e [l][j]); k= !++j){ p c[ 32]={0} ; d =*d-120?d:b ; if(s>2)J( k+=++c[b[j] -97]>1); if (!k) return b; } return d; } p*r(p* b){ _ k, l; for(_ j=k=l =0; j<5; ++ j) { signed char n=b[j] ,o=b[j-~5]+ ~0x66; (o?i .b[i.e]:i.c )[j]=n; !o? i.a[n]=!++k :O(i.d,n)|| (*(o<0?&i.a [n]:&i.d[i. f++])=l=n); } i.e += !! l; L(b, k); return E("" "xyzzy"); } _ main(_ n, char**v){ p *j=i .c-97, *l=j-11; n- 2?R("usage" ": %s dict" "\n",* v):5 ; ; FILE*k= fopen(*++v, "r"); if(!k ) return // perror(*v), 1; ; while( fgets(j, u^ n,k)) D(j); fclose (k); ; ; setbuf( stdout, 0); while(~-s){ printf("? " ); while(~( n=getchar() )&&n-10&&l< j)*l++=n; l <j&&R("inp" "ut: guess" " color\n") ;printf("%" ".5s\n",r(l =j+~10)); } return 0; }
In Twenty Eighth International Obfuscated C Code Contest
dbacar·Aug 3, 2025
This is epic: :) From : https://github.com/ioccc-src/winner/blob/master/2024/kurdyuk... This code draws the current moon phase to the console. So if you’re a lycanthrope, you can monitor the phase of the moon. #include <time.h> #include <stdio.h> a,b=44,x, y,z;main() {!a ?a=2551443,x= -b ,y=2-b,z=((time ( 0)-592531)%a<<9)/ a :putchar(++x>=a?x = -b,y+=4,10:x<0?x= x *x+y*y<b*b?a=1-x, - 1:x+1,32:"#."[( x <a*(~z&255)>> 8) ^z>>8]),y> b?0 :main();}
In Twenty Eighth International Obfuscated C Code Contest
MontyCarloHall·Jun 20, 2025
I understand the appeal of array languages — they provide very convenient shortcuts to common loop constructs in traditional imperative scalar languages. Their usefulness is manifest in the popularity of NumPy (and its derivatives, e.g. TensorFlow, PyTorch, JAX, etc.), MATLAB, Julia, R, and other Iverson Ghosts [0]. The rise of map/reduce/filter operations in common scalar programming languages is also testament to array languages' usefulness. I understand (though do not personally agree with) the appeal of extreme terseness — there are arguments to be made that maximizing information density minimizes context switching, since it reduces the amount of scrolling. Personally, I find that large displays and split buffers mitigate this issue, whereas the mental overhead of using my short-term memory to map dozens of single letter variables to
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semantic definitions is much higher than having to flip between splits/marks in my text editor. (The fact that the aforementioned Iverson Ghost languages are popular whereas APL and its derivatives are not is evidence that I'm aligned with most people in this regard.) I don't understand why people rarely make the terseness argument for non-array languages, even though it's just as easy to write tersely in them — the Obfuscated C Competition is a prime example [1]. Is it just due to the influence of APL, or is there something special about array languages that gives them a unique proclivity for terseness? [0] https://dev.to/bakerjd99/numpy-another-iverson-ghost-9mc [1] https://www.ioccc.org, https://github.com/ioccc-src/winner/blob/master/2020/ferguso...
In Klong: A Simple Array Language

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