add day 18

2024/18/part2.c

@@ -0,0 +1,221 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   part2.c                                            :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: tomoron <tomoron@student.42.fr>            +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2024/07/17 23:03:36 by tomoron           #+#    #+#             */
+/*   Updated: 2024/12/18 14:19:27 by tomoron          ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "libft/libft.h"
+
+typedef struct s_pos
+{
+	int x;
+	int y;
+} t_pos;
+
+typedef struct s_lst
+{
+	t_pos			pos;
+	uint32_t		score;
+	int				dir[2];
+	struct s_lst	*next;
+}	t_lst;
+
+static void *create_map(char **map, uint8_t fill, int bloc_size)
+{
+	int width;
+	int height;
+	int i;
+	void **res;
+
+	height = 0;
+	while(map[height])
+		height++;
+	width = 0;
+	while(map[0][width])
+		width++;
+	res = malloc((height + 1) * sizeof(void *));	
+	i = 0;
+	while(i < height)
+	{
+		res[i] = malloc((width + 1) * bloc_size);
+		ft_memset(res[i], fill, width * bloc_size);
+		((char **)res)[i][width * bloc_size] = 0;
+		i++;
+	}
+	return(res);
+}
+
+static int get_new_pos(t_lst **lst, char **vis, t_pos *pos, uint32_t *score, int *dir)
+{
+	t_lst *cur;
+	t_lst *sel;
+	t_lst *p_sel;
+	t_lst *prev;
+	uint32_t min;
+
+	if(!*lst)
+		return(0);
+	cur = *lst;
+	sel = 0;
+	p_sel = 0;
+	prev = 0;
+	min = -1;
+	while(cur)
+	{
+		if(cur->score < min)	
+		{
+			sel = cur;
+			p_sel = prev;
+			min = cur->score;
+		}
+		prev = cur;
+		cur = cur->next;
+	}
+	if(*lst && sel == *lst)
+		*lst = (*lst)->next;
+	if(p_sel)
+		p_sel->next = sel->next;
+	sel->next = 0;
+	*score = sel->score;
+	pos->x = sel->pos.x;
+	pos->y = sel->pos.y;
+	dir[0] = sel->dir[0];
+	dir[1] = sel->dir[1];
+	free(sel);
+	if(vis[pos->y][pos->x])
+		return(get_new_pos(lst, vis, pos, score, dir));
+	return(1);
+}
+
+static void add_lst(t_lst **lst, uint32_t score, t_pos pos, int dir[2])
+{
+	t_lst *new;
+	
+	new = malloc(sizeof(t_lst));
+	new->dir[0] = dir[0];
+	new->dir[1] = dir[1];
+	new->pos.x = pos.x;
+	new->pos.y = pos.y;
+	new->score = score;
+	new->next = *lst;
+	*lst = new;
+}
+
+static int	*rotate_dir(int dir[2], int inv, int *res)
+{
+	res[0] = 0;
+	res[1] = 0;
+	if(dir[0])	
+		res[1] = dir[0];	
+	if(dir[1])
+		res[0] = dir[1];
+	if(inv)
+	{
+		res[0] = -res[0];
+		res[1] = -res[1];
+	}
+	return(res);
+}
+
+static int is_valid_move(char **map, int y, int x)
+{
+	return(x >= 0 && y >= 0 && map[y] && map[y][x] == '.');
+}
+
+static uint32_t dijkstra(char **map, t_pos *pos, int corner)
+{
+	int dir[2];
+	int tmp[2];
+	char **visited;
+	uint32_t **dists;
+	t_lst *lst;
+	uint32_t score;
+
+	visited = create_map(map, 0, 1);
+	dists = create_map(map, 255, sizeof(uint32_t));
+	lst = 0;
+	add_lst(&lst, 0, *pos, (int [2]){0, 1});
+	while(get_new_pos(&lst, visited, pos, &score, dir))
+	{
+		if(dists[pos->y][pos->x] > score)
+			dists[pos->y][pos->x] = score;
+		visited[pos->y][pos->x] = 1;
+		if(map[pos->y][pos->x] == '#')
+			continue;
+		if(is_valid_move(map, pos->y + dir[0], pos->x + dir[1]))
+			add_lst(&lst, score + 1, (t_pos){pos->x + dir[1], pos->y + dir[0]}, dir);
+		rotate_dir(dir, 0, tmp);
+		if(is_valid_move(map, pos->y + tmp[0], pos->x + tmp[1]))
+			add_lst(&lst, score + 1, (t_pos){pos->x + tmp[1], pos->y + tmp[0]}, tmp);
+		rotate_dir(dir, 1, tmp);
+		if(is_valid_move(map, pos->y + tmp[0], pos->x + tmp[1]))
+			add_lst(&lst, score + 1, (t_pos){pos->x + tmp[1], pos->y + tmp[0]}, tmp);
+	}
+	if(dists[corner][corner] != (uint32_t) -1)
+		return(dists[corner][corner]);
+	return(0);
+}
+
+static char **create_map_size(int size, char fill)
+{
+	int i;
+	char **res;
+
+	res = malloc((size + 1) * sizeof(char *));
+	res[size] = 0;
+	i = 0;
+	while(i < size)
+	{
+		res[i] = malloc(size + 1);
+		res[i][size] = 0;
+		ft_memset(res[i], fill, size);
+		i++;
+	}
+	return(res);
+}
+
+static void get_nbrs(char *line, int *x, int *y)
+{
+	while(*line && !ft_isdigit(*line))
+		line++;
+	*x = ft_atoi(line);
+	while(ft_isdigit(*line))
+		line++;
+	while(*line && !ft_isdigit(*line))
+		line++;
+	*y = ft_atoi(line);
+}
+
+long int resolve_part2(char *input, char **split)
+{
+	char **map;
+	(void)input;
+	int x;
+	int y;
+	int i;
+
+	map = create_map_size(71, '.');
+	(void)map;
+	i = 1024;
+	while(split[i])
+	{
+		get_nbrs(split[i], &x, &y);
+		map[y][x] = '#';
+		if(dijkstra(map,&((t_pos){0, 0}), 70) == 0)
+		{
+			printf("real res : %d,%d\n", x, y);
+			return(i);
+		}
+		i++;
+	}
+	return(-1);
+}