Files
aoc/2024/15/part2.c
2024-12-15 19:13:01 +01:00

216 lines
3.9 KiB
C

/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* part2.c :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: tomoron <tomoron@student.42.fr> +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2024/07/17 23:03:36 by tomoron #+# #+# */
/* Updated: 2024/12/15 19:11:42 by tomoron ### ########.fr */
/* */
/* ************************************************************************** */
#include <stdio.h>
#include <stdlib.h>
#include "libft/libft.h"
typedef struct s_robot
{
int x;
int y;
} t_robot;
static t_robot get_robot(char **map)
{
int i;
int j;
i = 0;
while(map[i])
{
j = 0;
while(map[i][j])
{
if(map[i][j] == '@')
{
map[i][j] = '.';
return((t_robot){j, i});
}
j++;
}
i++;
}
return((t_robot){0, 0});
}
static int move(char **map, int dir[2], int pos[2], char c, int check)
{
int np[2];
np[0] = pos[0] + dir[0];
np[1] = pos[1] + dir[1];
if(map[np[0]][np[1]] == '#')
return(0);
if(map[np[0]][np[1]] == '.')
{
if(!check)
{
map[np[0]][np[1]] = c;
map[pos[0]][pos[1]] = '.';
}
return(1);
}
if((map[np[0]][np[1]] == ']'
&& move(map, dir, (int [2]){np[0], np[1] - 1},'[', check)
&& ((dir[1] == -1 && check) || move(map, dir, np, ']', check)))
|| (map[np[0]][np[1]] == '['
&& move(map, dir, (int [2]){np[0], np[1] + 1},']', check)
&& ((dir[1] == 1 && check) || move(map, dir, np, '[', check)))
)
{
if(!check)
{
map[np[0]][np[1]] = c;
map[pos[0]][pos[1]] = '.';
}
return(1);
}
return(0);
}
static long int calc_score(char **map)
{
int i;
int j;
long int res;
i = 0;
res = 0;
while(map[i] && map[i][0] == '#')
{
j = 0;
while(map[i][j])
{
if(map[i][j] == '[')
res += (100 * i) + j;
j++;
}
i++;
}
return(res);
}
static void exec_line(char **map, char *line, t_robot *robot)
{
int dirs[4][2] = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}};
int *dir;
while(*line)
{
switch(*line)
{
case '^':
dir = dirs[0];
break;
case 'v':
dir = dirs[1];
break;
case '<':
dir = dirs[2];
break;
default:
dir = dirs[3];
break;
}
if(move(map, dir, (int [2]){robot->y, robot->x}, map[robot->y][robot->x], 1))
{
move(map, dir, (int [2]){robot->y, robot->x}, map[robot->y][robot->x], 0);
robot->y += dir[0];
robot->x += dir[1];
}
line++;
}
}
void enlarge_line(char *src, char *dest)
{
int i;
i = 0;
while(*src)
{
if(*src == '#')
{
dest[i] = '#';
dest[i + 1] = '#';
}
if(*src == 'O')
{
dest[i] = '[';
dest[i + 1] = ']';
}
if(*src == '@')
{
dest[i] = '@';
dest[i + 1] = '.';
}
if(*src == '.')
{
dest[i] = '.';
dest[i + 1] = '.';
}
src++;
i += 2;
}
}
char **enlarge_map(char **map)
{
char **res;
int width;
int height;
int i;
height = 0;
while(map[height][0] == '#')
height++;
width = 0;
while(map[0][width])
width++;
width *= 2;
res = malloc((height + 1) * sizeof(char *));
res[height] = 0;
i = 0;
while(i < height)
{
res[i] = malloc(width + 1);
res[i][width] = 0;
enlarge_line(map[i], res[i]);
i++;
}
return(res);
}
long int resolve_part2(char *input, char **split)
{
(void)input;
long int res;
t_robot robot;
char **instr;
instr = split;
while(**instr == '#')
instr++;
split = enlarge_map(split);
robot = get_robot(split);
while(*instr)
{
exec_line(split, *instr, &robot);
instr++;
}
res = calc_score(split);
ft_free_str_arr(split);
return(res);
}