diff --git a/dynamic_programming/catalan_numbers.cpp b/dynamic_programming/catalan_numbers.cpp
index c99ea0026..a21a0a172 100644
--- a/dynamic_programming/catalan_numbers.cpp
+++ b/dynamic_programming/catalan_numbers.cpp
@@ -24,7 +24,7 @@ class catalan_numbers {
 
     value_type compute_next() {
         return std::transform_reduce(known.begin(), known.end(), known.rbegin(),
-                                     static_cast<value_type>(), std::plus<>(),
+                                     static_cast<value_type>(0), std::plus<>(),
                                      std::multiplies<>());
     }