Advent of Code Leaderboard 2025 / Day 2

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Leaderboard

	Name	Language	Tokens Sum	Tokens Part 1	Tokens Part 2	Last change
1	Frederik Bonfanti	Ruby	113	56	57	4 days ago
2	N. Adhikary	Python	151	76	75	21 hours ago
3	53142	Python	177	88	89	4 days ago
4	Abbas Moosajee	Python	180	85	95	4 days ago
5	Vadzim Kapichenka	Kotlin	184	82	102	11 hours ago
6	progheal	C++	198	85	113	4 days ago
7	Valentin Slawicek	Kotlin	201	92	109	3 days ago
8	Akke	C	352	159	193	3 days ago
9	Wim Jeantine-Glenn	Python	926	463	463	4 days ago
10	Allan Taylor	Python	10138	138	-	4 days ago

Solutions with 1 unsolved part get a penalty of 10000 tokens (indicated with "-").

Rules

You're welcome to participate alone or in a team.
You may submit multiple solutions and explore different programming languages.
Stick to the standard library of your language, no further dependencies/libraries, except the ones which OneCompiler provides (e.g. NumPy for Python).
Ensure your code aligns to the template (Python, Rust, Go, Kotlin, JavaScript, C#, TypeScript, C++, Java, C, Swift, Scala, Ruby, Bash), reading the puzzle input from stdin (terminated with end-of-file), and printing the solution to stdout.
Please refrain from making network requests, reading data from files, or storing data in variable/function/class names for reflection.
Your code must be able to process all valid Advent of Code inputs. Golfcoder might reevaluate correctness of your solution with different inputs after your submission.

193 tokens in C for part 2 by Akke

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#include<stdlib.h>

intmain(void)
{
charbuf[999],s[999],*r=buf,*p;
longsum=0,fst,lst,n,is_invalid;
gets(buf);
while(*r){
fst=atol(r);while(*r!='-')r++;
lst=-atol(r);while(r[-1]!=','&&r[-1])r++;
while(fst<=lst){
sprintf(s,"%lu",fst);
for(n=1,is_invalid=0;n<=strlen(s)/2;n++){
for(p=s;!strncmp(s,p,n);)
p+=n;
is_invalid|=(!(strlen(s)%n)&!strlen(p));
}
sum+=(fst++)*is_invalid;
}
}
printf("%lu\n",sum);
return0;
}