diff --git a/latex/code/lib/variantvisit.cpp b/latex/code/lib/variantvisit.cpp
index 0f834f7..2932b46 100644
--- a/latex/code/lib/variantvisit.cpp
+++ b/latex/code/lib/variantvisit.cpp
@@ -11,7 +11,7 @@ struct MyVisitor
         std::cout << "string: " << s << '\n';
     }
     void operator() (long double d) const {
-        std::cotu << "double: " << d << '\n';
+        std::cout << "double: " << d << '\n';
     }
 };
 
@@ -23,4 +23,4 @@ int main()
     std::visit(MyVisitor(), var);   // 调用string的operator()
     var = 42.7;
     std::visit(MyVisitor(), var);   // 调用long double的operator()
-}
\ No newline at end of file
+}