day1 part2

2023/day1/src/main.rs

@@ -1,3 +1,5 @@
+use regex::Regex;
+use std::collections::HashMap;
 use std::fs::File;
 use std::io::{self, BufRead};
 use std::path::Path;
@@ -7,7 +9,13 @@ fn main() -> io::Result<()> {
     let mut result = 0;
     if let Ok(lines) = read_lines("./src/input") {
         for line in lines.flatten() {
-            if let Some(value) = extract_digit_pair_sum(&line) {
+            print!("{} -> ", line);
+
+            // No need for .as_str(), just pass &line
+            let mut replaced_line = replace_written_digits(&line);
+            replaced_line = replace_written_digits(&replaced_line);
+            println!("{}", replaced_line);
+            if let Some(value) = extract_digit_pair_sum(&replaced_line) {
                 println!("Current result: {} + {} = {}", result, value, result + value);
                 result += value;
             }
@@ -15,14 +23,40 @@ fn main() -> io::Result<()> {
     }
 
     println!("Final result: {}", result);
+
     Ok(())
 }
 
+fn replace_written_digits<T: AsRef<str>>(input: T) -> String {
+    // Create a map of written digits to their numeric counterparts
+    let digit_map = HashMap::from([
+        ("one", "1ne"),
+        ("two", "2wo"),
+        ("three", "3hree"),
+        ("four", "4our"),
+        ("five", "5ive"),
+        ("six", "6ix"),
+        ("seven", "7even"),
+        ("eight", "8ight"),
+        ("nine", "9ine"),
+    ]);
+
+    // Create a regex that matches the written digits
+    let re = Regex::new(r"(?:one|two|three|four|five|six|seven|eight|nine)").unwrap();
+
+    // Replace all occurrences of written digits with their numeric counterparts
+    re.replace_all(input.as_ref(), |caps: &regex::Captures| {
+        // Access the full match (use caps.get(0) instead of caps[1])
+        let matched_word = caps.get(0).unwrap().as_str();
+        digit_map.get(matched_word).unwrap().to_string()
+    }).to_string()
+}
+
 // Extracts first and last digits from a line, forms a number, and returns the sum
 fn extract_digit_pair_sum(line: &str) -> Option<i32> {
     let first_digit = get_first_digit(line)?;
     let last_digit = get_last_digit(line)?;
-    
+
     let digit_str = format!("{}{}", first_digit, last_digit);
     digit_str.parse::<i32>().ok()
 }