feat: complete day 1

rust/2021/src/day_01.rs

@@ -1,15 +1,42 @@
-pub fn solve_part1(input: &str) -> &str {
+use itertools::Itertools;
+
+fn solve_part1(input: &str) -> i32 {
     input
+        .lines()
+        .filter_map(|s| s.parse().ok())
+        .tuple_windows::<(i32, i32)>()
+        .fold(0, |a, (l, r)| a + if l < r { 1 } else { 0 })
 }
 
-pub fn solve_part2(input: &str) -> &str {
+fn solve_part2(input: &str) -> i32 {
     input
+        .lines()
+        .filter_map(|s| s.parse().ok())
+        .tuple_windows::<(i32, i32, i32)>()
+        .map(|(l, m, r)| l + m + r)
+        .tuple_windows()
+        .fold(0, |a, (l, r)| a + if l < r { 1 } else { 0 })
 }
 
 pub fn run(input: String) {
     println!("--- Part 1 ---");
     println!("Answer: {}", solve_part1(&input));
-    print!("\n");
+    println!();
     println!("--- Part 2 ---");
-    println!("Answer: {}", solve_part1(&input))
+    println!("Answer: {}", solve_part2(&input))
+}
+
+#[cfg(test)]
+mod tests {
+    const EXAMPLE_INPUT: &str = "199\n200\n208\n210\n200\n207\n240\n269\n260\n263";
+
+    #[test]
+    fn part1() {
+        assert_eq!(super::solve_part1(EXAMPLE_INPUT), 7);
+    }
+
+    #[test]
+    fn part2() {
+        assert_eq!(super::solve_part2(EXAMPLE_INPUT), 5);
+    }
 }

rust/2021/src/day_02.rs

@@ -0,0 +1,18 @@
+fn solve_part1(input: &str) -> i32 {
+    todo!()
+}
+
+fn solve_part2(input: &str) -> i32 {
+    todo!()
+}
+
+pub fn run(input: String) {
+    println!("--- Part 1 ---");
+    println!("Answer: {}", solve_part1(&input));
+    println!();
+    println!("--- Part 2 ---");
+    println!("Answer: {}", solve_part2(&input))
+}
+
+#[cfg(test)]
+mod tests {}

rust/2021/src/lib.rs

@@ -1,5 +1,6 @@
 mod day_01;
+mod day_02;
 
 pub fn run(input: String) {
-    day_01::run(input);
+    day_02::run(input);
 }

rust/2021/src/main.rs

@@ -1,4 +1,4 @@
 fn main() {
-    let input = std::fs::read_to_string("./input/2020/day20.txt").expect("open input file");
+    let input = std::fs::read_to_string("./input/2021/day2.txt").expect("open input file");
     advent_of_code_2021::run(input);
 }