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Differences From Artifact [1416b27373]:

To Artifact [e64fb4bd5d]:


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#include <ctype.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "aocdailies.h"
#include "aocutils.h"






























/* === aoc202409 =======================================================
   WOW! input consists of a 20,000 long string of numbers!
   Make an array of blocks, each with either -1 or the fileid
   For Part Two: make an array of blocks with the encoded value of
(fileid * 10) + length, or, when empty, the negative length
===================================================================== */








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#include <ctype.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "aocdailies.h"
#include "aocutils.h"

/* === aoc202422 =======================================================
===================================================================== */
static long long unsigned mix(long long unsigned a, long long unsigned b) {
    long long unsigned tmp = a ^ b;
    return tmp;
}

static long long unsigned prune(long long unsigned a) {
    return a % 16777216;
}

void aoc202422(char *data, size_t len) {
    (void)len; // unused argument
    long long unsigned sum2000 = 0;
    char *key = strtok(data, "\n");
    while (key) {
        long long unsigned secret;
        if (sscanf(key, "%llu", &secret) != 1) break;
        for (int k = 0; k < 2000; k++) {
            secret = prune(mix(secret * 64, secret));
            secret = prune(mix(secret / 32, secret));
            secret = prune(mix(secret * 2048, secret));
        }
        sum2000 += secret;
        key = strtok(NULL, "\n");
    }
    printf("The sum of all 2000th secrets is {%llu}.\n", sum2000);
}

/* === aoc202409 =======================================================
   WOW! input consists of a 20,000 long string of numbers!
   Make an array of blocks, each with either -1 or the fileid
   For Part Two: make an array of blocks with the encoded value of
(fileid * 10) + length, or, when empty, the negative length
===================================================================== */