Implement 2025 - Day 5 - Part 2

2025/05.rs

@@ -0,0 +1,46 @@
+---cargo
+---
+
+static CONTENT: &'static str = include_str!("./inputs/05_1.txt");
+
+fn main() {
+    let mut ranges: Vec<_> = CONTENT.lines().map(|l| l.trim()).take_while(|l| !l.is_empty()).map(|r| {
+        let (start, end) = r.split_once('-').unwrap();
+        let start = start.parse::<usize>().unwrap();
+        let end = end.parse::<usize>().unwrap();
+
+        start..=end
+    }).collect();
+
+    loop {
+        let result: Option<(usize, usize)> = ranges.iter().enumerate().find_map(|(idx, r)| {
+            ranges.iter().enumerate().filter(|(o_idx, _)| idx != *o_idx).find_map(|(o_idx, other)| {
+                r.contains(other.start()).then_some((idx, o_idx))
+            })
+        });
+
+        let (idx, o_idx) = match result {
+            Some(r) => r,
+            None => break,
+        };
+
+        let first = ranges[idx].clone();
+        let second = ranges[o_idx].clone();
+
+        let new_range_start: usize = *first.start().min(second.start());
+        let new_range_end: usize = *first.end().max(second.end());
+
+        let new_range = new_range_start..=new_range_end;
+
+        println!("Merge\n{:?} +\n{:?} =\n{:?}", first, second, new_range);
+        ranges[idx] = new_range;
+        ranges.remove(o_idx);
+    }
+
+    ranges.sort_by_key(|v| (*v.start(), *v.end()));
+
+    println!("Ranges: \n{:#?}", ranges);
+
+    let result: usize = ranges.iter().map(|r| r.clone().count()).sum();
+    println!("Result: {:?}", result);
+}

2025/inputs/05_example.txt

@@ -0,0 +1,11 @@
+3-5
+10-14
+16-20
+12-18
+
+1
+5
+8
+11
+17
+32