Attempting more optimization on day12 part 1

This commit is contained in:
Timothy Warren 2022-12-22 11:21:22 -05:00
parent 9c2665ab61
commit 8b01dcc2cf
1 changed files with 136 additions and 90 deletions

View File

@ -23,6 +23,134 @@ impl Grid<char> {
fn find_pos(&self, value: char) -> Option<usize> {
self.vec.iter().position(|item| *item == value)
}
fn print(&self) {
for r in 0usize..self.num_rows() {
let range = self.row_first_idx(r)..=self.row_last_idx(r);
let line: String = self.vec[range].iter().collect();
println!("{}", line);
}
}
fn get_index_for_move(&self, from: usize, dir: Direction) -> Option<usize> {
let (mut x, mut y) = self.idx_xy(from);
match dir {
Direction::Up => {
if y >= 1 {
y -= 1;
} else {
return None;
}
}
Direction::Down => {
if y < self.num_rows() - 1 {
y += 1;
} else {
return None;
}
}
Direction::Left => {
if x >= 1 {
x -= 1;
} else {
return None;
}
}
Direction::Right => {
if x < self.num_cols() - 1 {
x += 1;
} else {
return None;
}
}
};
Some(self.xy_idx(x, y))
}
fn is_valid_move(&self, start: usize, end: usize) -> bool {
// Is the item within the grid?
let start_char = self.get(start);
let end_char = self.get(end);
if start_char.is_none() || end_char.is_none() {
return false;
}
// Is the elevation change 0 or 1?
let start_char = *start_char.unwrap();
let end_char = *end_char.unwrap();
let start_char = start_char
.to_digit(36)
.expect(&format!("Should be a digit: {}", start_char)) as i32;
let end_char = end_char
.to_digit(36)
.expect(&format!("Should be a digit: {}", end_char)) as i32;
let diff = end_char - start_char;
if diff > 1 || diff < 0 || end_char < start_char {
return false;
}
let (start_x, start_y) = self.idx_xy(start);
let (end_x, end_y) = self.idx_xy(end);
let x_diff = usize::abs_diff(end_x, start_x);
let y_diff = usize::abs_diff(end_y, start_y);
// Have we moved 0 or 1 in a cardinal direction?
match (x_diff, y_diff) {
(0, 0) | (0, 1) | (1, 0) => true,
_ => false,
}
}
fn find_valid_moves(&self, start: usize) -> Vec<usize> {
[
Direction::Up,
Direction::Down,
Direction::Left,
Direction::Right,
]
.into_iter()
.map(|d| self.get_index_for_move(start, d))
.filter(|m| m.is_some())
.map(|m| m.unwrap())
.filter(|m| self.is_valid_move(start, *m))
.collect()
}
fn has_valid_neighbor(&self, idx: usize) -> bool {
self.find_valid_moves(idx).len() > 0
}
fn filter_invalid(&mut self, from: usize) {
let (ch, col_indexes, row_indexes) = {
let ch = self.get(from).unwrap();
let (col, row) = self.idx_xy(from);
let col_indexes = self.get_column_indexes(col);
let row_indexes = self.get_row_indexes(row);
(ch, col_indexes, row_indexes)
};
self.vec = self.vec
.clone()
.into_iter()
.enumerate()
.map(|(idx, c)| {
if c != *ch {
return c;
}
return if self.has_valid_neighbor(idx) && (col_indexes.contains(&idx) || row_indexes.contains(&idx)) {
c
} else {
'0'
}
})
.collect();
}
}
// ----------------------------------------------------------------------------
@ -137,97 +265,13 @@ impl Pathfinder {
self.end_idx = end;
self.grid.vec[start] = 'a';
self.grid.vec[end] = 'z';
self.grid.filter_invalid(start);
self.tree.idx = start;
}
fn get_index_for_move(&self, from: usize, dir: Direction) -> Option<usize> {
let (mut x, mut y) = self.grid.idx_xy(from);
match dir {
Direction::Up => {
if y >= 1 {
y -= 1;
} else {
return None;
}
}
Direction::Down => {
if y < self.grid.num_rows() - 1 {
y += 1;
} else {
return None;
}
}
Direction::Left => {
if x >= 1 {
x -= 1;
} else {
return None;
}
}
Direction::Right => {
if x < self.grid.num_cols() - 1 {
x += 1;
} else {
return None;
}
}
};
Some(self.grid.xy_idx(x, y))
}
fn is_valid_move(&self, start: usize, end: usize) -> bool {
// Is the item within the grid?
let start_char = self.grid.get(start);
let end_char = self.grid.get(end);
if start_char.is_none() || end_char.is_none() {
return false;
}
// Is the elevation change 0 or 1?
let start_char = *start_char.unwrap();
let end_char = *end_char.unwrap();
let start_char = start_char
.to_digit(36)
.expect(&format!("Should be a digit: {}", start_char)) as i32;
let end_char = end_char
.to_digit(36)
.expect(&format!("Should be a digit: {}", end_char)) as i32;
let diff = end_char - start_char;
if diff > 1 || diff < 0 || end_char < start_char {
return false;
}
let (start_x, start_y) = self.grid.idx_xy(start);
let (end_x, end_y) = self.grid.idx_xy(end);
let x_diff = usize::abs_diff(end_x, start_x);
let y_diff = usize::abs_diff(end_y, start_y);
// Have we moved 0 or 1 in a cardinal direction?
match (x_diff, y_diff) {
(0, 0) | (0, 1) | (1, 0) => true,
_ => false,
}
}
fn find_valid_moves(&self, start: usize) -> Vec<usize> {
[
Direction::Up,
Direction::Down,
Direction::Left,
Direction::Right,
]
.into_iter()
.map(|d| self.get_index_for_move(start, d))
.filter(|m| m.is_some())
.map(|m| m.unwrap())
.filter(|m| self.is_valid_move(start, *m))
.collect()
}
fn add_children(&mut self, node: &mut Node, idx: usize) {
let possible_moves = self.find_valid_moves(idx);
let possible_moves = self.grid.find_valid_moves(idx);
for m in possible_moves {
if node.contains(m) {
@ -273,7 +317,8 @@ fn main() {
let file_str = include_str!("input.txt");
let mut finder = Pathfinder::from_file_str(file_str);
dbg!(finder);
// dbg!(finder);
finder.grid.print();
// let shortest_path = finder.find_shortest_path();
// println!("Part 1: Fewest steps: {}", shortest_path.get_len());
@ -295,13 +340,14 @@ mod tests {
fn find_valid_moves() {
let finder = get_finder();
assert_eq!(finder.find_valid_moves(finder.start_idx), vec![8, 1]);
assert_eq!(finder.find_valid_moves(8), vec![0, 16, 9]);
assert_eq!(finder.grid.find_valid_moves(finder.start_idx), vec![8, 1]);
assert_eq!(finder.grid.find_valid_moves(8), vec![0, 16, 9]);
}
#[test]
fn find_shortest_path() {
let mut finder = get_finder();
finder.grid.print();
let shortest = finder.find_shortest_path();
assert_eq!(shortest.get_len(), 31);