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#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define COUNT 1024
#define FIRST 100
#define LAST 1000
int row(char *s)
{
int low = 0;
int high = 128;
for (char *p = s; *p && *p != 'R' && *p != 'L'; p++) {
if (*p == 'F') {
high -= 2 << (5 - (p - s));
} else if (*p == 'B') {
low += 2 << (5 - (p - s));
}
}
return low;
}
int col(char *s)
{
int low = 0;
int high = 8;
for (char *p = s + 7; *(p + 1); p++) {
if (*p == 'L') {
high -= 2 << (1 - (p - (s + 7)));
} else if (*p == 'R') {
low += 2 << (1 - (p - (s + 7)));
}
}
if (*(s + 9) == 'R')
return high - 1;
else if (*(s + 9) == 'L')
return low;
else
return 0;
}
int compare(const void *a, const void *b)
{
int int_a = *((int *)a);
int int_b = *((int *)b);
if (int_a == int_b)
return 0;
else if (int_a < int_b)
return -1;
else
return 1;
}
static int ids[COUNT] = { 0 };
int part_one(FILE *fp)
{
int res = 0;
char *line = NULL;
size_t len = 0;
int i = 0;
while (getline(&line, &len, fp) != -1) {
int id = row(line) * 8 + col(line);
if (id > res)
res = id;
ids[i] = id;
i++;
}
return res;
}
int part_two()
{
int res = 0;
qsort(ids, COUNT, sizeof(int), compare);
for (int i = 1; i < COUNT - 1; ++i) {
if (ids[i] == 0)
continue;
if (ids[i] != ids[i + 1] && ids[i] != ids[i - 1] && i > FIRST && i < LAST)
res = ids[i];
}
return res;
}
int main(int argc, char *argv[])
{
FILE *fp = fopen("input", "r");
if (!fp)
exit(EXIT_FAILURE);
clock_t tic = clock();
printf("%d\n", part_one(fp));
printf("%d\n", part_two());
clock_t toc = clock();
printf("TIME: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC);
fclose(fp);
return 0;
}
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