Solution for day 12

main
Inga 🏳‍🌈 4 years ago
parent 6daf2f69ff
commit bc4b69a40a
  1. 9
      day12-hard/Cargo.toml
  2. 130
      day12-hard/src/main.rs
  3. 9
      day12/Cargo.toml
  4. 126
      day12/src/main.rs

@ -0,0 +1,9 @@
[package]
name = "day12-hard"
version = "0.1.0"
authors = ["inga-lovinde <52715130+inga-lovinde@users.noreply.github.com>"]
edition = "2018"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]

@ -0,0 +1,130 @@
use std::io::{self, BufRead};
use std::error::Error;
use std::str::FromStr;
enum Command {
East(i64),
West(i64),
North(i64),
South(i64),
Left(i64),
Right(i64),
Forward(i64),
}
impl FromStr for Command {
type Err = Box<dyn Error>;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let first_char = match s.chars().next() {
Some(ch) => ch,
_ => {
return Err(Box::from("string is empty"));
}
};
let remainder: String = s.chars().skip(1).collect();
let value: i64 = remainder.parse()?;
Ok(match first_char {
'E' => Self::East(value),
'W' => Self::West(value),
'N' => Self::North(value),
'S' => Self::South(value),
'L' => Self::Left(value),
'R' => Self::Right(value),
'F' => Self::Forward(value),
_ => {
return Err(Box::from("unsupported first character"));
}
})
}
}
struct State {
ship_offset_north: i64,
ship_offset_east: i64,
waypoint_ship_offset_north: i64,
waypoint_ship_offset_east: i64,
}
impl State {
fn get_angle_cos(angle: i64) -> i64 {
match angle {
0 => 1,
90 => 0,
180 => -1,
270 => 0,
_ => panic!("Unsupported angle"),
}
}
fn get_angle_sin(angle: i64) -> i64 {
match angle {
0 => 0,
90 => 1,
180 => 0,
270 => -1,
_ => panic!("Unsupported angle"),
}
}
pub fn new() -> Self {
Self {
ship_offset_north: 0,
ship_offset_east: 0,
waypoint_ship_offset_north: 1,
waypoint_ship_offset_east: 10,
}
}
pub fn apply_command(&self, command: Command) -> Self {
match command {
Command::East(distance) => Self {
waypoint_ship_offset_east: self.waypoint_ship_offset_east + distance,
..*self
},
Command::West(distance) => Self {
waypoint_ship_offset_east: self.waypoint_ship_offset_east - distance,
..*self
},
Command::North(distance) => Self {
waypoint_ship_offset_north: self.waypoint_ship_offset_north + distance,
..*self
},
Command::South(distance) => Self {
waypoint_ship_offset_north: self.waypoint_ship_offset_north - distance,
..*self
},
Command::Left(angle) => Self {
waypoint_ship_offset_east: self.waypoint_ship_offset_east * Self::get_angle_cos(angle) - self.waypoint_ship_offset_north * Self::get_angle_sin(angle),
waypoint_ship_offset_north: self.waypoint_ship_offset_east * Self::get_angle_sin(angle) + self.waypoint_ship_offset_north * Self::get_angle_cos(angle),
..*self
},
Command::Right(angle) => Self {
waypoint_ship_offset_east: self.waypoint_ship_offset_east * Self::get_angle_cos(angle) + self.waypoint_ship_offset_north * Self::get_angle_sin(angle),
waypoint_ship_offset_north: -self.waypoint_ship_offset_east * Self::get_angle_sin(angle) + self.waypoint_ship_offset_north * Self::get_angle_cos(angle),
..*self
},
Command::Forward(times) => Self {
ship_offset_east: self.ship_offset_east + self.waypoint_ship_offset_east * times,
ship_offset_north: self.ship_offset_north + self.waypoint_ship_offset_north * times,
..*self
},
}
}
pub fn get_manhattan_norm(&self) -> i64 {
self.ship_offset_east.abs() + self.ship_offset_north.abs()
}
}
fn main() {
let stdin = io::stdin();
let mut state = State::new();
for line in stdin.lock().lines() {
state = state.apply_command(line.unwrap().parse().unwrap());
}
println!("{}", state.get_manhattan_norm());
}

@ -0,0 +1,9 @@
[package]
name = "day12"
version = "0.1.0"
authors = ["inga-lovinde <52715130+inga-lovinde@users.noreply.github.com>"]
edition = "2018"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]

@ -0,0 +1,126 @@
use std::io::{self, BufRead};
use std::error::Error;
use std::str::FromStr;
enum Command {
East(i64),
West(i64),
North(i64),
South(i64),
Left(i64),
Right(i64),
Forward(i64),
}
impl FromStr for Command {
type Err = Box<dyn Error>;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let first_char = match s.chars().next() {
Some(ch) => ch,
_ => {
return Err(Box::from("string is empty"));
}
};
let remainder: String = s.chars().skip(1).collect();
let value: i64 = remainder.parse()?;
Ok(match first_char {
'E' => Self::East(value),
'W' => Self::West(value),
'N' => Self::North(value),
'S' => Self::South(value),
'L' => Self::Left(value),
'R' => Self::Right(value),
'F' => Self::Forward(value),
_ => {
return Err(Box::from("unsupported first character"));
}
})
}
}
struct State {
offset_north: i64,
offset_east: i64,
angle: i64,
}
impl State {
fn get_angle_cos(&self) -> i64 {
match self.angle {
0 => 1,
90 => 0,
180 => -1,
270 => 0,
_ => panic!("Unsupported angle"),
}
}
fn get_angle_sin(&self) -> i64 {
match self.angle {
0 => 0,
90 => 1,
180 => 0,
270 => -1,
_ => panic!("Unsupported angle"),
}
}
pub fn new() -> Self {
Self {
offset_north: 0,
offset_east: 0,
angle: 0
}
}
pub fn apply_command(&self, command: Command) -> Self {
match command {
Command::East(distance) => Self {
offset_east: self.offset_east + distance,
..*self
},
Command::West(distance) => Self {
offset_east: self.offset_east - distance,
..*self
},
Command::North(distance) => Self {
offset_north: self.offset_north + distance,
..*self
},
Command::South(distance) => Self {
offset_north: self.offset_north - distance,
..*self
},
Command::Left(angle) => Self {
angle: (self.angle + angle).rem_euclid(360),
..*self
},
Command::Right(angle) => Self {
angle: (self.angle - angle).rem_euclid(360),
..*self
},
Command::Forward(distance) => Self {
offset_east: self.offset_east + self.get_angle_cos() * distance,
offset_north: self.offset_north + self.get_angle_sin() * distance,
..*self
},
}
}
pub fn get_manhattan_norm(&self) -> i64 {
self.offset_east.abs() + self.offset_north.abs()
}
}
fn main() {
let stdin = io::stdin();
let mut state = State::new();
for line in stdin.lock().lines() {
state = state.apply_command(line.unwrap().parse().unwrap());
}
println!("{}", state.get_manhattan_norm());
}
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