finished day 01 part 2

day-01/src/part2.rs

@@ -0,0 +1,59 @@
+use color_eyre::Result;
+
+pub fn process(input: &str) -> Result<u32> {
+    let sum: u32 = input.lines().map(process_line).sum();
+
+    Ok(sum)
+}
+
+fn process_line(line: &str) -> u32 {
+    let mut it = (0..line.len()).filter_map(|index| {
+        let reduced_line = &line[index..];
+        let result = if reduced_line.starts_with("one") {
+            Some(1)
+        } else if reduced_line.starts_with("two") {
+            Some(2)
+        } else if reduced_line.starts_with("three") {
+            Some(3)
+        } else if reduced_line.starts_with("four") {
+            Some(4)
+        } else if reduced_line.starts_with("five") {
+            Some(5)
+        } else if reduced_line.starts_with("six") {
+            Some(6)
+        } else if reduced_line.starts_with("seven") {
+            Some(7)
+        } else if reduced_line.starts_with("eight") {
+            Some(8)
+        } else if reduced_line.starts_with("nine") {
+            Some(9)
+        } else {
+            reduced_line.chars().next().unwrap().to_digit(10)
+        };
+        result
+    });
+
+    let first = it.next().expect("Should be a number");
+
+    match it.last() {
+        Some(num) => first * 10 + num,
+        None => first * 10 + first,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_process() -> Result<()> {
+        let input = "two1nine
+eightwothree
+abcone2threexyz
+xtwone3four
+4nineeightseven2
+zoneight234
+7pqrstsixteen";
+        assert_eq!(281, process(input)?);
+        Ok(())
+    }
+}