add day 6

day06/src/main.rs

@@ -0,0 +1,56 @@
+use std::collections::HashMap;
+
+#[cfg(debug_assertions)]
+const FILENAME: &str = "example.txt";
+#[cfg(not(debug_assertions))]
+const FILENAME: &str = "input.txt";
+
+fn main() {
+    let binding = std::fs::read_to_string(FILENAME).unwrap();
+    let data: Vec<_> = binding.lines().collect();
+
+    part1(&data);
+    part2(&data);
+}
+
+fn part2(data: &[&str]) {
+    let mut counts = vec![HashMap::new(); data[0].len()];
+
+    for message in data {
+        message.chars().enumerate().for_each(|(idx, c)| {
+            counts[idx].entry(c).and_modify(|i| *i += 1).or_insert(1);
+        });
+    }
+
+    for count in counts {
+        let the_char = count
+            .iter()
+            .min_by_key(|(_, val)| **val)
+            .map(|(c, _)| c)
+            .unwrap();
+
+        print!("{the_char}");
+    }
+    println!();
+}
+
+fn part1(data: &[&str]) {
+    let mut counts = vec![HashMap::new(); data[0].len()];
+
+    for message in data {
+        message.chars().enumerate().for_each(|(idx, c)| {
+            counts[idx].entry(c).and_modify(|i| *i += 1).or_insert(1);
+        });
+    }
+
+    for count in counts {
+        let the_char = count
+            .iter()
+            .max_by_key(|(_, val)| **val)
+            .map(|(c, _)| c)
+            .unwrap();
+
+        print!("{the_char}");
+    }
+    println!();
+}