feat: day 1!

src/bin/day_1.rs

@@ -0,0 +1,83 @@
+use aoc_2022::prelude::*;
+
+type Input = Vec<String>;
+
+fn parse(s: &str) -> Result<Input> {
+    Ok(s.lines()
+        .map(ToOwned::to_owned)
+        .filter(|line| line.len() != 0)
+        .collect::<Vec<_>>())
+}
+
+const DIGITS: [(&str, &str); 18] = [
+    ("one", "1"),
+    ("two", "2"),
+    ("three", "3"),
+    ("four", "4"),
+    ("five", "5"),
+    ("six", "6"),
+    ("seven", "7"),
+    ("eight", "8"),
+    ("nine", "9"),
+    ("1", "1"),
+    ("2", "2"),
+    ("3", "3"),
+    ("4", "4"),
+    ("5", "5"),
+    ("6", "6"),
+    ("7", "7"),
+    ("8", "8"),
+    ("9", "9"),
+];
+
+#[aoc(day = 1, parse = parse, test_cases = ["day_1.txt"])]
+fn day_1(mut input: Input) -> Result<()> {
+    // Part 1
+    println!("Part one: ");
+    let mut total = 0;
+    for line in &input {
+        let digits = line.chars()
+            .filter(|c| c.is_digit(10))
+            .collect::<Vec<_>>();
+        if digits.len() == 0 {
+            continue;
+        }
+        let first_digit = digits[0];
+        let last_digit = digits[digits.len() - 1];
+        let value = format!("{first_digit}{last_digit}")
+            .parse::<u32>()
+            .expect("digits to be digits");
+        total += value;
+    }
+    println!("{total}");
+
+    // Part 2
+    println!("Part two: ");
+    let mut total = 0;
+    for line in &input {
+        let mut first_digit = None;
+        let mut last_digit = None;
+        for i in 0..(line.len()) {
+            for (word, digit) in DIGITS {
+                if i + word.len() <= line.len() {
+                    if &line[i..(i+word.len())] == word {
+                        if first_digit.is_none() {
+                            first_digit = Some(digit.to_owned());
+                        }
+                        last_digit = Some(digit.to_owned());
+                        break;
+                    }
+                }
+            }
+        }
+        let (first_digit, last_digit) = (first_digit.expect("there to be a first digit"), last_digit.expect("there to be a last digit"));
+        let value = format!("{first_digit}{last_digit}")
+            .parse::<u32>()
+            .expect("digits to be digits");
+        println!("{value}");
+        total += value;
+    }
+    println!("{total}");
+
+    Ok(())
+}

test_cases/day_1.txt

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+two1nine
+eightwothree
+abcone2threexyz
+xtwone3four
+4nineeightseven2
+zoneight234
+7pqrstsixteen