From: Lukáš Jiřiště <gymnazium.jiriste@gmail.com>
Date: Sat, 9 Dec 2023 17:35:27 +0000 (+0100)
Subject: Add solution to first part of day 8
X-Git-Url: https://git.ljiriste.work/?a=commitdiff_plain;h=eee5d053efc81a0cba8eadedc408105edd1e8509;p=AoC_2023.git

Add solution to first part of day 8
---

diff --git a/8/8.c b/8/8.c
new file mode 100644
index 0000000..c77da29
--- /dev/null
+++ b/8/8.c
@@ -0,0 +1,169 @@
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include "libft.h"
+
+#define ID_LEN 3
+#define INIT_CAP 4
+
+struct s_snode
+{
+	char	id[ID_LEN];
+	char	id_l[ID_LEN];
+	char	id_r[ID_LEN];
+};
+typedef struct s_snode	t_snode;
+
+struct s_inode
+{
+	char	id[ID_LEN];
+	size_t	index_l;
+	size_t	index_r;
+};
+typedef struct s_inode	t_inode;
+
+union u_node
+{
+	t_snode	snode;
+	t_inode	inode;
+};
+typedef union u_node	t_node;
+
+struct	s_node_vec
+{
+	size_t	capacity;
+	size_t	size;
+	t_node	*array;
+};
+typedef struct s_node_vec	t_node_vec;
+
+int enlarge_vec(t_node_vec *vec)
+{
+    t_node *tmp;
+
+	if (vec->capacity == 0)
+	{
+		vec->array = NULL;
+		vec->size = 0;
+		vec->capacity = INIT_CAP;
+	}
+    tmp = vec->array;
+    vec->array = ft_calloc(vec->capacity * 2, sizeof(*vec->array));
+    if (!vec->array)
+    {
+        vec->array = tmp;
+        return (1);
+    }
+    vec->capacity *= 2;
+    ft_memcpy(vec->array, tmp, vec->size * sizeof(*vec->array));
+    free(tmp);
+    return (0);
+}
+
+void	translate_nodes(t_node_vec *str_map)
+{
+	char	left[ID_LEN];
+	char	right[ID_LEN];
+	size_t	i;
+	size_t	j;
+
+	i = 0;
+	while (i < str_map->size)
+	{
+		ft_memcpy(left, str_map->array[i].snode.id_l, ID_LEN);
+		ft_memcpy(right, str_map->array[i].snode.id_r, ID_LEN);
+		j = 0;
+		while (j < str_map->size)
+		{
+			if (!ft_strncmp(str_map->array[j].snode.id, left, ID_LEN))
+				str_map->array[i].inode.index_l = j;
+			if (!ft_strncmp(str_map->array[j].snode.id, right, ID_LEN))
+				str_map->array[i].inode.index_r = j;
+			++j;
+		}
+		++i;
+	}
+	return ;
+}
+
+void	add_node(t_node_vec *str_map, const char *line)
+{
+	if (str_map->size >= str_map->capacity)
+		enlarge_vec(str_map);
+	ft_memcpy(&(str_map->array[str_map->size].snode.id), line, ID_LEN);
+	ft_memcpy(&(str_map->array[str_map->size].snode.id_l), line + ID_LEN + 4, ID_LEN);
+	ft_memcpy(&(str_map->array[str_map->size].snode.id_r), line + 2 * ID_LEN + 6, ID_LEN);
+	++str_map->size;
+	return ;
+}
+
+int	parse(const char *filename, t_node_vec *ind_map, char **inst)
+{
+	int			fd;
+	char		*line;
+
+	fd = open(filename, O_RDONLY);
+	if (fd < 0)
+		return (2);
+	*inst = get_next_line(fd);
+	(*inst)[ft_strlen(*inst) - 1] = '\0';
+	free(get_next_line(fd));
+	line = get_next_line(fd);
+	while (line)
+	{
+		add_node(ind_map, line);
+		free(line);
+		line = get_next_line(fd);
+	}
+	translate_nodes(ind_map);
+	close(fd);
+	return (0);
+}
+
+size_t	find_ind(const t_node_vec ind_map, const char wanted[ID_LEN])
+{
+	size_t	i;
+
+	i = 0;
+	while (i < ind_map.size)
+	{
+		if (!ft_strncmp(ind_map.array[i].inode.id, wanted, ID_LEN))
+			return (i);
+		++i;
+	}
+	return (-1);
+}
+int	steps_to_traverse(const t_node_vec ind_map, const char *inst, const char end_id[ID_LEN])
+{
+	size_t	i;
+	int		result;
+
+	i = find_ind(ind_map, "AAA");
+	result = 0;
+	while (ft_strncmp(ind_map.array[i].inode.id, end_id, ID_LEN))
+	{
+		if (inst[result % ft_strlen(inst)] == 'R')
+			i = ind_map.array[i].inode.index_r;
+		else
+			i = ind_map.array[i].inode.index_l;
+		++result;
+	}
+	return (result);
+}
+
+int	main(int argc, char **argv)
+{
+	t_node_vec	ind_map;
+	char		*inst;
+
+	if (argc != 2)
+		return (1);
+	ind_map.capacity = 0;
+	parse(argv[1], &ind_map, &inst);
+	ft_printf("%i steps are needed to reach ZZZ.\n", steps_to_traverse(ind_map, inst, "ZZZ"));
+	return (0);
+	free(ind_map.array);
+	free(inst);
+}
+