diff --git a/.gitignore b/.gitignore
index bcb41c7d..524baeab 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
-/book_out
+/book
 /dataset
 /target
 /Cargo.lock
diff --git a/book.toml b/book.toml
index cb5159dc..9604de87 100644
--- a/book.toml
+++ b/book.toml
@@ -3,14 +3,14 @@
 title = "数据结构与算法 Rust 语言实现"
 description = ""
 authors = ["Shaohua <shaohua@biofan.org>"]
-src = "book"
+src = "src"
 language = "zh-CN"
 
 [rust]
 edition = "2021"
 
 [build]
-build-dir = "book_out"
+build-dir = "book"
 create-missing = false
 
 [output.html]
diff --git a/sorts/src/selection_sort.rs b/sorts/src/selection_sort.rs
index 4fc16fdb..a445e2fb 100644
--- a/sorts/src/selection_sort.rs
+++ b/sorts/src/selection_sort.rs
@@ -29,7 +29,7 @@ pub fn selection_sort<T>(list: &mut [T])
 where
     T: PartialOrd,
 {
-    if list.is_empty() {
+    if list.len() < 2 {
         return;
     }
     let len = list.len();
diff --git a/book/SUMMARY.md b/src/SUMMARY.md
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