From 4ed8d6d2413d55989dc1faf83481b45241c2dc13 Mon Sep 17 00:00:00 2001
From: Jacob <jacob@katniss.top>
Date: Wed, 20 May 2026 22:02:44 -0400
Subject: [PATCH] feat: get first or last element of `OneToManyUniqueBTreeMap`

---
 src/one_to_many.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/one_to_many.rs b/src/one_to_many.rs
index c17f9c2..f986b30 100644
--- a/src/one_to_many.rs
+++ b/src/one_to_many.rs
@@ -42,6 +42,14 @@ where
         self.right_to_left.get(right)
     }
 
+    pub fn first_left_and_rights(&self) -> Option<(&Left, &BTreeSet<Right>)> {
+        self.left_to_rights.first_key_value()
+    }
+
+    pub fn last_left_and_rights(&self) -> Option<(&Left, &BTreeSet<Right>)> {
+        self.left_to_rights.last_key_value()
+    }
+
     pub fn remove_left(&mut self, left: &Left) -> Option<(Left, BTreeSet<Right>)> {
         let (left, rights) = self.left_to_rights.remove_entry(left)?;