diff --git a/include/bits/include-all.hpp b/include/bits/include-all.hpp
index b75e18e..b160e83 100644
--- a/include/bits/include-all.hpp
+++ b/include/bits/include-all.hpp
@@ -28,6 +28,7 @@
 #include <tuple>
 #include <type_traits>
 #include <unordered_set>
+#include <unordered_map>
 #include <utility>
 #include <valarray>
 #include <vector>