aoc

diff --git a/2021/day-01/src/main.rs b/2021/day-01/src/main.rs
index e2a4a1f81bfd26b1a9732484f41d161858a3ea24..c11ed9680031355cf121fe5bf4ff14748771c243 100644
--- a/2021/day-01/src/main.rs
+++ b/2021/day-01/src/main.rs
@@ -5,9 +5,25 @@ fn main() -> io::Result<()> {
     let stdin = io::stdin();
     let lines = stdin.lock().lines();
 
-    for line in lines {
-        println!("{:?}", line?);
-    }
+    let nums: Vec<i32> = lines.map(|x| x.unwrap().parse().unwrap()).collect();
+    let nums2 = nums.clone();
+
+    // Part 1: size is 1
+    // Part 2: size is 3
+    let window_size = 3;
+
+    let niter = nums.windows(window_size);
+    let niter2 = nums2[1..nums2.len() - 1].windows(window_size);
+
+    let res = niter.zip(niter2).fold(1, |acc, (x, y)| {
+        if y.iter().sum::<i32>() > x.iter().sum::<i32>() {
+            acc + 1
+        } else {
+            acc
+        }
+    });
+
+    println!("{:?}", res);
 
     Ok(())
 }