From 92225c05db65dd6986340a9325c0e3540480cda4 Mon Sep 17 00:00:00 2001
From: Eric Fistons <eric@pedr0.net>
Date: Thu, 12 Jun 2025 22:34:50 +0200
Subject: [PATCH] Fix challenge

---
 src/main.rs | 56 +++++++++++++++--------------------------------------
 1 file changed, 16 insertions(+), 40 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 27bc2d2..f9be344 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,44 +1,20 @@
-#[derive(PartialEq, Debug)]
-enum Order {
-    Up,
-    Down,
-    Stable,
-    Uninit,
-}
-
+#[allow(dead_code)]
 fn find_peaks_and_valleys(values: &[isize]) -> Vec<usize> {
-    let mut peaks_and_valleys = vec![];
-    let mut order = Order::Uninit;
-    for i in 1..values.len() {
-        let previous = values[i - 1];
-        let current = values[i];
-
-        let new_order = match current - previous {
-            0 => Order::Stable,
-            x if x > 0 => Order::Up,
-            x if x < 0 => Order::Down,
-            _ => unreachable!(),
-        };
-
-        println!(
-            "Compared {previous} ({}) and {current} ({}). Current order is {order:?}, new order is {new_order:?}",
-            i - 1,
-            i
-        );
-
-        if order != new_order && order != Order::Uninit {
-            peaks_and_valleys.push(i);
-            println!("Order changed, pushing {}", i)
-        }
-        order = new_order;
-    }
-
-    peaks_and_valleys
+    values
+        .windows(3)
+        .enumerate()
+        .flat_map(|(idx, arr)| {
+            let (a, b, c) = (arr[0], arr[1], arr[2]);
+            if (b > a && b > c) || (b < a && b < c) {
+                Some(idx + 1)
+            } else {
+                None
+            }
+        })
+        .collect()
 }
 
-fn main() {
-    println!("{:?}", find_peaks_and_valleys(&[1, 2, 3, 4, 1, 8]));
-}
+fn main() {}
 
 #[cfg(test)]
 mod tests {
@@ -47,7 +23,7 @@ mod tests {
     #[test]
     pub fn test() {
         assert_eq!(
-            find_peaks_and_valleys(&[1, 2, 1, 3, 4, 5, 4, 5, 2, 1, 2, 3]),
+            find_peaks_and_valleys(&[1, 2, 1, 3, 4, 5, 4, 3, 2, 1, 2, 3]),
             vec![1, 2, 5, 9]
         );
     }
@@ -61,7 +37,7 @@ mod tests {
     pub fn test_up_and_down() {
         assert_eq!(
             find_peaks_and_valleys(&[1, 0, 1, 0, 1, 0]),
-            vec![1, 2, 3, 4, 5]
+            vec![1, 2, 3, 4]
         );
     }