day04 both

src/tasks/day04.rs

@@ -0,0 +1,149 @@
+use chrono::prelude::*;
+use chrono::Duration;
+use chrono::NaiveDateTime;
+use std::collections::HashMap;
+use utils;
+
+enum Activity {
+    Starts(u32),
+    FallsAsleep,
+    Awakens,
+}
+
+#[derive(PartialEq)]
+enum State {
+    Asleep,
+    Awake,
+}
+
+pub fn task1() {
+    use self::Activity::*;
+    let input = utils::read_file("input/day04.txt");
+    let mut input: Vec<_> = input
+        .lines()
+        .map(|line| {
+            // [1518-10-26 00:01] Guard #1069 begins shift
+            let time = NaiveDateTime::parse_from_str(&line[1..=16], "%Y-%m-%d %H:%M").unwrap();
+            let activity = if line.contains("falls asleep") {
+                Activity::FallsAsleep
+            } else if line.contains("wakes up") {
+                Activity::Awakens
+            } else {
+                let number: u32 = line.split(' ').find(|part| part.starts_with("#")).unwrap()[1..]
+                    .parse()
+                    .unwrap();
+                Activity::Starts(number)
+            };
+            (time, activity)
+        }).collect();
+    input.sort_by_key(|it| it.0);
+
+    let mut current_id: u32 = 0;
+    let mut current_state = State::Awake;
+    let mut last_time = input[0].0;
+    let mut sleep_map: HashMap<u32, [usize; 60]> = HashMap::new();
+    let minute = Duration::minutes(1);
+    for (time, activity) in input.into_iter() {
+        // for all minutes since last time slot fill arrays
+        let mut iter_time = last_time.clone();
+        while iter_time < time {
+            if current_state == State::Asleep && iter_time.hour() == 0 {
+                sleep_map.entry(current_id).or_insert([0; 60])[iter_time.minute() as usize] += 1;
+            }
+            iter_time += minute;
+        }
+
+        match activity {
+            Starts(id) => {
+                current_state = State::Awake;
+                current_id = id;
+            }
+            FallsAsleep => current_state = State::Asleep,
+            Awakens => current_state = State::Awake,
+        }
+        last_time = time;
+    }
+
+    let sleeper = sleep_map
+        .iter()
+        .map(|(id, schedule)| (id, schedule.iter().sum::<usize>()))
+        .max_by_key(|it| it.1)
+        .unwrap();
+    println!("Sleeper: {:?}", sleeper);
+
+    let worst_minute = sleep_map
+        .get(sleeper.0)
+        .unwrap()
+        .iter()
+        .enumerate()
+        .max_by_key(|it| it.1)
+        .unwrap()
+        .0;
+
+    println!("Worst minute: {}", worst_minute);
+
+    println!("Result: {}", *sleeper.0 as usize * worst_minute);
+}
+
+pub fn task2() {
+    use self::Activity::*;
+    let input = utils::read_file("input/day04.txt");
+    let mut input: Vec<_> = input
+        .lines()
+        .map(|line| {
+            // [1518-10-26 00:01] Guard #1069 begins shift
+            let time = NaiveDateTime::parse_from_str(&line[1..=16], "%Y-%m-%d %H:%M").unwrap();
+            let activity = if line.contains("falls asleep") {
+                Activity::FallsAsleep
+            } else if line.contains("wakes up") {
+                Activity::Awakens
+            } else {
+                let number: u32 = line.split(' ').find(|part| part.starts_with("#")).unwrap()[1..]
+                    .parse()
+                    .unwrap();
+                Activity::Starts(number)
+            };
+            (time, activity)
+        }).collect();
+    input.sort_by_key(|it| it.0);
+
+    let mut current_id: u32 = 0;
+    let mut current_state = State::Awake;
+    let mut last_time = input[0].0;
+    let mut sleep_map: HashMap<u32, [usize; 60]> = HashMap::new();
+    let minute = Duration::minutes(1);
+    for (time, activity) in input.into_iter() {
+        // for all minutes since last time slot fill arrays
+        let mut iter_time = last_time.clone();
+        while iter_time < time {
+            if current_state == State::Asleep && iter_time.hour() == 0 {
+                sleep_map.entry(current_id).or_insert([0; 60])[iter_time.minute() as usize] += 1;
+            }
+            iter_time += minute;
+        }
+
+        match activity {
+            Starts(id) => {
+                current_state = State::Awake;
+                current_id = id;
+            }
+            FallsAsleep => current_state = State::Asleep,
+            Awakens => current_state = State::Awake,
+        }
+        last_time = time;
+    }
+
+    let sleeper = sleep_map
+        .iter()
+        .max_by_key(|(_, array)| array.iter().max())
+        .unwrap();
+    let worst_minute = sleeper
+        .1
+        .iter()
+        .enumerate()
+        .max_by_key(|it| it.1)
+        .unwrap()
+        .0;
+
+    println!("Result 2: {}", *sleeper.0 as usize * worst_minute);
+}

src/tasks/mod.rs

@@ -1,3 +1,4 @@
 pub mod day01;
 pub mod day02;
 pub mod day03;
+pub mod day04;