aoc-2019-c

Advent of Code 2019 Solutions in C
git clone https://git.sinitax.com/sinitax/aoc-2019-c
Log | Files | Refs | README | sfeed.txt

main.c (2702B)

      1#include "aoc.h"
      2#include "allocator.h"
      3#include "hmap.h"
      4#include "dvec_s.h"
      5#include "util.h"
      6
      7#include <assert.h>
      8#include <errno.h>
      9#include <stdio.h>
     10#include <string.h>
     11#include <stdint.h>
     12#include <stdlib.h>
     13
     14struct planet {
     15	char *name;
     16	struct planet *parent;
     17	struct dvec children;
     18};
     19
     20struct hmap planets;
     21
     22struct planet *
     23planets_get(const char *name)
     24{
     25	struct hmap_link *link;
     26	struct hmap_key key;
     27
     28	key.p = name;
     29	link = hmap_get(&planets, key);
     30	return link ? link->value._p : NULL;
     31}
     32
     33struct planet *
     34planets_add(const char *name)
     35{
     36	struct planet *planet;
     37	char *key;
     38
     39	planet = malloc(sizeof(struct planet));
     40	if (!planet) die("main: planets_add: malloc");
     41
     42	planet->name = aprintf("%s", name);
     43	planet->parent = NULL;
     44	dvec_init(&planet->children, sizeof(struct planet *),
     45		3, &stdlib_heap_allocator);
     46
     47	key = aprintf("%s", name);
     48	assert(!hmap_add(&planets, (struct hmap_key) {.p = key},
     49		(struct hmap_val) {.p = planet}));
     50
     51	return planet;
     52}
     53
     54void
     55planets_init()
     56{
     57	struct planet *parent, *child, **slot;
     58	const char *pos, *end;
     59	char buf[256], *sep;
     60
     61	hmap_init(&planets, 100, hmap_str_hash,
     62		hmap_str_keycmp, &stdlib_heap_allocator);
     63
     64	pos = aoc.input;
     65	end = aoc.input + aoc.input_size;
     66	while (readtok(buf, sizeof(buf), '\n', &pos, end)) {
     67		sep = strchr(buf, ')');
     68		if (!sep) die("main: bad format");
     69		*sep = '\0';
     70
     71		parent = planets_get(buf);
     72		if (!parent) parent = planets_add(buf);
     73
     74		child = planets_get(sep + 1);
     75		if (!child) child = planets_add(sep + 1);
     76
     77		slot = dvec_add_slot(&parent->children);
     78		*slot = child;
     79
     80		if (child->parent) die("main unexpected parent");
     81		child->parent = parent;
     82	}
     83}
     84
     85void
     86planets_deinit()
     87{
     88	struct hmap_iter iter;
     89	struct planet *p;
     90
     91	for (HMAP_ITER(&planets, iter)) {
     92		free(iter.link->key._p);
     93		p = iter.link->value._p;
     94		dvec_deinit(&p->children);
     95		free(p->name);
     96		free(p);
     97	}
     98
     99	hmap_deinit(&planets);
    100}
    101
    102void
    103part1(void)
    104{
    105	struct hmap_iter iter;
    106	const struct planet *p;
    107	int orbits;
    108
    109	planets_init();
    110
    111	orbits = 0;
    112	for (HMAP_ITER(&planets, iter)) {
    113		p = iter.link->value.p;
    114		while (p->parent) {
    115			orbits += 1;
    116			p = p->parent;
    117		}
    118	}
    119
    120	aoc.answer = aprintf("%i", orbits);
    121	aoc.solution = "119831";
    122
    123	planets_deinit();
    124}
    125
    126void
    127part2(void)
    128{
    129	struct planet *p1, *p2, *san, *you;
    130	int s1, s2;
    131
    132	planets_init();
    133
    134	san = planets_get("SAN");
    135	if (!san) die("main: missing planet SAN");
    136	you = planets_get("YOU");
    137	if (!you) die("main: missing planet YOU");
    138
    139	for (s1 = 0, p1 = you; p1; p1 = p1->parent, s1++) {
    140		for (s2 = 0, p2 = san; p2; p2 = p2->parent, s2++) {
    141			if (!strcmp(p1->name, p2->name))
    142				goto exit;
    143		}
    144	}
    145exit:
    146
    147	aoc.answer = aprintf("%i", s1 + s2 - 2);
    148	aoc.solution = "322";
    149
    150	planets_deinit();
    151}