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#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef PART1
#define DIGITS ((size_t)(2))
#else
#define DIGITS ((size_t)(12))
#endif
int
main(void)
{
FILE *fp = fopen("input", "r");
if (fp == nullptr)
err(EXIT_FAILURE, "failed to open input");
char *buf = nullptr;
size_t acc, bufsz;
ssize_t n;
acc = bufsz = 0;
while ((n = getline(&buf, &bufsz, fp)) != -1) {
if (buf[n - 1] == '\n')
buf[--n] = 0;
char digits[DIGITS + 1];
memcpy(digits, buf, DIGITS);
digits[DIGITS] = 0;
for (size_t i = 1; i < n - DIGITS + 1; i++) {
for (size_t j = 0; j < DIGITS; j++) {
if (buf[i + j] > digits[j])
memcpy(digits + j, buf + i + j, DIGITS - j);
}
}
acc += (size_t)strtol(digits, nullptr, 10);
}
if (ferror(fp))
err(EXIT_FAILURE, "failed to read record");
fclose(fp);
printf("%zu\n", acc);
return EXIT_SUCCESS;
}
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