From 9ec5e10c0b379e599d47463ab224d82e6b30d180 Mon Sep 17 00:00:00 2001
From: hal8174 <henning.lindemann@pm.me>
Date: Fri, 15 Nov 2024 03:27:56 +0100
Subject: [PATCH] Minor performance optimization

---
 vertex_cover/src/owned.rs | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/vertex_cover/src/owned.rs b/vertex_cover/src/owned.rs
index 3dc3d31..177ae33 100644
--- a/vertex_cover/src/owned.rs
+++ b/vertex_cover/src/owned.rs
@@ -1,5 +1,3 @@
-use std::collections::HashSet;
-
 #[derive(Debug)]
 struct Vertex {
     name: u16,
@@ -50,7 +48,12 @@ impl Graph {
 
         for &e in &vertex.edges {
             let i = self.index[e as usize];
-            self.vertices[i as usize].edges.retain(|&o| o != v);
+            let p = self.vertices[i as usize]
+                .edges
+                .iter()
+                .position(|&o| o == v)
+                .unwrap();
+            self.vertices[i as usize].edges.swap_remove(p);
         }
         // dbg!(&self.index);