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#include <limits.h>
#include <openssl/md5.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#define FORLINE \
char *line = NULL; \
size_t len = 0; \
while (getline(&line, &len, fp) != EOF)
#define FREELINE \
if (line) \
free(line)
#define FORCH \
char ch = 0; \
while ((ch = fgetc(fp)) != EOF)
#define WHOLE \
fseek(fp, 0, SEEK_END); \
long fsize = ftell(fp); \
fseek(fp, 0, SEEK_SET); \
char *data = malloc(fsize + 1); \
fread(data, 1, fsize, fp); \
data[fsize] = 0; \
data[fsize--] = 0
#define FREEWHOLE free(data)
static int part_one(FILE *fp)
{
int res = 0;
WHOLE;
char *string = malloc(fsize + 64);
strcpy(string, data);
while (1) {
res++;
int cnt = sprintf(string + fsize, "%d", res);
char out[64] = { 0 };
unsigned char *hash =
MD5((unsigned char *)string, fsize + cnt, (unsigned char *)out);
/* for (int i = 0; i < 16; i++) */
/* printf("%02x", hash[i]); */
/* putchar('\n'); */
int sum = 0;
for (int i = 0; i < 2; i++)
sum += hash[i];
sum += hash[2] & 0xf0;
if (sum == 0)
break;
}
free(string);
FREEWHOLE;
return res;
}
static int part_two(FILE *fp)
{
int res = 0;
WHOLE;
char *string = malloc(fsize + 64);
strcpy(string, data);
while (1) {
res++;
int cnt = sprintf(string + fsize, "%d", res);
char out[64] = { 0 };
unsigned char *hash =
MD5((unsigned char *)string, fsize + cnt, (unsigned char *)out);
/* for (int i = 0; i < 16; i++) */
/* printf("%02x", hash[i]); */
/* putchar('\n'); */
int sum = 0;
for (int i = 0; i < 3; i++)
sum += hash[i];
if (sum == 0)
break;
}
free(string);
FREEWHOLE;
return res;
}
int main(int argc, char *argv[])
{
(void)argc;
(void)argv;
FILE *fp = fopen("input", "r");
if (!fp)
exit(EXIT_FAILURE);
clock_t tic = clock();
printf("%d\n", part_one(fp));
rewind(fp);
printf("%d\n", part_two(fp));
clock_t toc = clock();
printf("TIME: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC);
fclose(fp);
return 0;
}
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