day(01): add solution

Signed-off-by: Matej Focko <mfocko@redhat.com>

samples/day01_1.txt

@@ -0,0 +1,4 @@
+1abc2
+pqr3stu8vwx
+a1b2c3d4e5f
+treb7uchet

samples/day01_2.txt

@@ -0,0 +1,7 @@
+two1nine
+eightwothree
+abcone2threexyz
+xtwone3four
+4nineeightseven2
+zoneight234
+7pqrstsixteen

src/bin/day01.rs

@@ -0,0 +1,67 @@
+use aoc_2023::*;
+
+type Output1 = i32;
+type Output2 = Output1;
+
+const NUMBERS: [&str; 9] = [
+    "one", "two", "three", "four", "five", "six", "seven", "eight", "nine",
+];
+
+struct Day01 {
+    lines: Vec<String>,
+}
+impl Solution<Output1, Output2> for Day01 {
+    fn new<P: AsRef<Path>>(pathname: P) -> Self {
+        Self {
+            lines: file_to_lines(pathname),
+        }
+    }
+
+    fn part_1(&mut self) -> Output1 {
+        self.lines
+            .iter()
+            .map(|line| {
+                let digits = line.chars().filter_map(|c| c.to_digit(10)).collect_vec();
+
+                (10 * digits.first().unwrap() + digits.last().unwrap()) as i32
+            })
+            .sum()
+    }
+
+    fn part_2(&mut self) -> Output2 {
+        self.lines
+            .iter()
+            .map(|line| {
+                let mut digits: Vec<i32> = vec![];
+
+                for (i, c) in line.chars().enumerate() {
+                    if let Some(d) = c.to_digit(10) {
+                        digits.push(d as i32);
+                    }
+
+                    if let Some(d) = NUMBERS
+                        .iter()
+                        .enumerate()
+                        .find_map(|(n, nstr)| {
+                            if line[i..].starts_with(nstr) {
+                                Some(n as i32 + 1)
+                            } else {
+                                None
+                            }
+                        })
+                    {
+                        digits.push(d)
+                    }
+                }
+
+                10 * digits.first().unwrap() + digits.last().unwrap()
+            })
+            .sum()
+    }
+}
+
+fn main() -> Result<()> {
+    Day01::main()
+}
+
+test_sample!(day_01, Day01, 142, 281);