diff --git a/2024/07.cpp b/2024/07.cpp
index f5c7082..37213e6 100644
--- a/2024/07.cpp
+++ b/2024/07.cpp
@@ -4,9 +4,12 @@
 #include <boost/fusion/adapted/std_tuple.hpp>
 #include <boost/spirit/include/qi.hpp>
 
+#include <cstdint>
+#include <iostream>
 #include <optional>
 #include <stack>
 #include <tuple>
+#include <vector>
 
 namespace qi = boost::spirit::qi;
 
@@ -29,7 +32,7 @@ auto calibrated(
   std::vector<std::uint64_t> const& numbers
 ) -> bool
 {
-  if (numbers.size() == 0) { return false; }
+  if (numbers.empty()) { return false; }
 
   auto work = std::stack<std::tuple<std::size_t, std::uint64_t>>{};
   work.emplace(numbers.size() - 1, target);