Day 6

Cargo.lock

@@ -41,3 +41,11 @@ version = "0.1.0"
 [[package]]
 name = "d05t2"
 version = "0.1.0"
+
+[[package]]
+name = "d06t1"
+version = "0.1.0"
+
+[[package]]
+name = "d06t2"
+version = "0.1.0"

Cargo.toml

@@ -12,4 +12,6 @@ members = [
     "d04t2",
     "d05t1",
     "d05t2",
+    "d06t1",
+    "d06t2",
 ]

d01t1/src/lib.rs

@@ -0,0 +1,23 @@
+pub fn d01t1(input: &str) -> u32 {
+    input
+        .lines()
+        .map(|line| {
+            let digits = line
+                .chars()
+                .filter(char::is_ascii_digit)
+                .collect::<Vec<char>>();
+            let mut num_str = digits.first().unwrap().to_string();
+            num_str.push(*digits.last().unwrap());
+            num_str.parse::<u32>().unwrap()
+        })
+        .sum::<u32>()
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_d01t1() {
+        let input = include_str!("../demo_input.txt");
+        assert_eq!(d01t1(input), 142);
+    }
+}

d01t1/src/main.rs

@@ -1,31 +1,8 @@
 use std::fs::read_to_string;
 
+use d01t1::d01t1;
+
 fn main() {
     let input = read_to_string("input.txt").unwrap();
     println!("d01t1: {}", d01t1(&input));
 }
-
-fn d01t1(input: &str) -> u32 {
-    input
-        .lines()
-        .map(|line| {
-            let digits = line
-                .chars()
-                .filter(char::is_ascii_digit)
-                .collect::<Vec<char>>();
-            let mut num_str = digits.first().unwrap().to_string();
-            num_str.push(*digits.last().unwrap());
-            num_str.parse::<u32>().unwrap()
-        })
-        .sum::<u32>()
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    #[test]
-    fn test_d01t1() {
-        let input = include_str!("../demo_input.txt");
-        assert_eq!(d01t1(input), 142);
-    }
-}

d06t1/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "d06t1"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

d06t1/demo_input.txt

@@ -0,0 +1,2 @@
+Time:      7  15   30
+Distance:  9  40  200

d06t1/src/main.rs

@@ -0,0 +1,45 @@
+use std::fs::read_to_string;
+
+fn main() {
+    let input = read_to_string("input.txt").unwrap();
+    println!("d06t1: {}", d06t1(&input));
+}
+
+pub fn d06t1(input: &str) -> usize {
+    let mut lines = input.lines();
+    let mut timings = lines.next().unwrap().split_whitespace();
+    let mut distances = lines.next().unwrap().split_whitespace();
+    assert!(lines.next().is_none());
+    assert_eq!(timings.next().unwrap(), "Time:");
+    assert_eq!(distances.next().unwrap(), "Distance:");
+    let timings = timings
+        .map(str::parse::<usize>)
+        .map(Result::unwrap)
+        .collect::<Vec<_>>();
+    let distances = distances
+        .map(str::parse::<usize>)
+        .map(Result::unwrap)
+        .collect::<Vec<_>>();
+    timings
+        .into_iter()
+        .zip(distances)
+        .map(min_press_time)
+        .reduce(|a, b| a * b)
+        .unwrap()
+}
+
+fn min_press_time((time, distance): (usize, usize)) -> usize {
+    (1..=time)
+        .filter(|acceleration_time| acceleration_time * (time - acceleration_time) > distance)
+        .count()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_d06t1() {
+        let input = include_str!("../demo_input.txt");
+        assert_eq!(d06t1(input), 288);
+    }
+}

d06t2/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "d06t2"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

d06t2/demo_input.txt

@@ -0,0 +1,2 @@
+Time:      7  15   30
+Distance:  9  40  200

d06t2/src/main.rs

@@ -0,0 +1,34 @@
+use std::fs::read_to_string;
+
+fn main() {
+    let input = read_to_string("input.txt").unwrap();
+    println!("d06t2: {}", d06t2(&input));
+}
+
+pub fn d06t2(input: &str) -> usize {
+    let mut lines = input.lines();
+    let mut timings = lines.next().unwrap().split_whitespace();
+    let mut distances = lines.next().unwrap().split_whitespace();
+    assert!(lines.next().is_none());
+    assert_eq!(timings.next().unwrap(), "Time:");
+    assert_eq!(distances.next().unwrap(), "Distance:");
+    let timing = timings.collect::<String>().parse::<usize>().unwrap();
+    let distance = distances.collect::<String>().parse::<usize>().unwrap();
+    min_press_time((timing, distance))
+}
+
+fn min_press_time((time, distance): (usize, usize)) -> usize {
+    (1..=time)
+        .filter(|acceleration_time| acceleration_time * (time - acceleration_time) > distance)
+        .count()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_d06t2() {
+        let input = include_str!("../demo_input.txt");
+        assert_eq!(d06t2(input), 71503);
+    }
+}