Second star.

src/main.rs

@@ -1,6 +1,7 @@
 use std::env;
 use std::fs;
 use std::io::{self, BufRead};
+use std::collections::BinaryHeap;
 
 fn main() {
     let args: Vec<String> = env::args().collect();
@@ -15,15 +16,26 @@ fn main() {
     let file = fs::File::open(filename).unwrap();
     let lines = io::BufReader::new(file).lines();
 
-    let mut max_cals: u32 = 0;
+    let mut heap = BinaryHeap::new();
+
     let mut cur_cals: u32 = 0;
     for l in lines {
         if let Ok(cals) = l.unwrap().parse::<u32>() {
             cur_cals += cals;
         } else {
-            max_cals = max_cals.max(cur_cals);
-            println!("new cals: {}, max so far: {}", cur_cals, max_cals);
+            heap.push(cur_cals);
+            println!("new cals: {}, max so far: {}", cur_cals, heap.peek().unwrap());
             cur_cals = 0;
         };
     }
+
+    if cur_cals > 0 {
+        heap.push(cur_cals);
+    }
+
+    let mut vec = heap.into_sorted_vec();
+    vec.dedup();
+
+    let total: u32 = vec.iter().rev().take(3).sum();
+    println!("calories of top 3 are: {}", total);
 }