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#include "aoc.h"
#include "allocator.h"
#include "hmap.h"
#include "dvec_s.h"
#include "util.h"
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <stdlib.h>
struct planet {
char *name;
struct planet *parent;
struct dvec children;
};
struct hmap planets;
struct planet *
planets_get(const char *name)
{
struct hmap_link *link;
struct hmap_key key;
key.p = name;
link = hmap_get(&planets, key);
return link ? link->value._p : NULL;
}
struct planet *
planets_add(const char *name)
{
struct planet *planet;
char *key;
planet = malloc(sizeof(struct planet));
if (!planet) die("main: planets_add: malloc");
planet->name = aprintf("%s", name);
planet->parent = NULL;
dvec_init(&planet->children, sizeof(struct planet *),
3, &stdlib_heap_allocator);
key = aprintf("%s", name);
assert(!hmap_add(&planets, (struct hmap_key) {.p = key},
(struct hmap_val) {.p = planet}));
return planet;
}
void
planets_init()
{
struct planet *parent, *child, **slot;
const char *pos, *end;
char buf[256], *sep;
hmap_init(&planets, 100, hmap_str_hash,
hmap_str_keycmp, &stdlib_heap_allocator);
pos = aoc.input;
end = aoc.input + aoc.input_size;
while (readtok(buf, sizeof(buf), '\n', &pos, end)) {
sep = strchr(buf, ')');
if (!sep) die("main: bad format");
*sep = '\0';
parent = planets_get(buf);
if (!parent) parent = planets_add(buf);
child = planets_get(sep + 1);
if (!child) child = planets_add(sep + 1);
slot = dvec_add_slot(&parent->children);
*slot = child;
if (child->parent) die("main unexpected parent");
child->parent = parent;
}
}
void
planets_deinit()
{
struct hmap_iter iter;
struct planet *p;
for (HMAP_ITER(&planets, iter)) {
free(iter.link->key._p);
p = iter.link->value._p;
dvec_deinit(&p->children);
free(p->name);
free(p);
}
hmap_deinit(&planets);
}
void
part1(void)
{
struct hmap_iter iter;
const struct planet *p;
int orbits;
planets_init();
orbits = 0;
for (HMAP_ITER(&planets, iter)) {
p = iter.link->value.p;
while (p->parent) {
orbits += 1;
p = p->parent;
}
}
aoc.answer = aprintf("%i", orbits);
aoc.solution = "119831";
planets_deinit();
}
void
part2(void)
{
struct planet *p1, *p2, *san, *you;
int s1, s2;
planets_init();
san = planets_get("SAN");
if (!san) die("main: missing planet SAN");
you = planets_get("YOU");
if (!you) die("main: missing planet YOU");
for (s1 = 0, p1 = you; p1; p1 = p1->parent, s1++) {
for (s2 = 0, p2 = san; p2; p2 = p2->parent, s2++) {
if (!strcmp(p1->name, p2->name))
goto exit;
}
}
exit:
aoc.answer = aprintf("%i", s1 + s2 - 2);
aoc.solution = "322";
planets_deinit();
}
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