diff --git a/codes/rust/chapter_computational_complexity/time_complexity.rs b/codes/rust/chapter_computational_complexity/time_complexity.rs
index b421b3007..8fb4121a2 100644
--- a/codes/rust/chapter_computational_complexity/time_complexity.rs
+++ b/codes/rust/chapter_computational_complexity/time_complexity.rs
@@ -86,7 +86,7 @@ fn exp_recur(n: i32) -> i32 {
     if n == 1 {
         return 1;
     }
-    exp_recur(n - 1) + exp_recur(n - 1)
+    exp_recur(n - 1) + exp_recur(n - 1) + 1
 }
 
 /* 对数阶（循环实现） */