add cpp

cpp/.gitignore

@@ -0,0 +1,3 @@
+build
+*cmake-build-debug*
+*CMakeFiles*

cpp/test.cpp

@@ -0,0 +1,32 @@
+#include "./fast_io/include/fast_io.h"
+#include "./fast_io/include/fast_io_device.h"
+#include "na_nbt_impl.hpp"
+#include <vector>
+int main(int argc, char** argv)
+{
+    {
+        fast_io::native_file_loader nfl(fast_io::mnp::os_c_str(argv[1]));
+        std::system("pause");
+        {
+            std::vector<std::byte> data{
+                reinterpret_cast<std::byte*>(nfl.begin()),
+                reinterpret_cast<std::byte*>(nfl.end())};
+            fast_io::io::println(fast_io::out(), "test big_endian read in_place with bound_check");
+
+            using na::nbt::nbt_type;
+            std::system("pause");
+            auto beforetime = std::chrono::steady_clock::now();
+            auto document{na::nbt::read<true, true, std::endian::big>(std::span(data))};
+            auto aftertime = std::chrono::steady_clock::now();
+            std::system("pause");
+            double duration_second = std::chrono::duration<double>(aftertime - beforetime).count();
+            auto root = document.value<nbt_type::tag_compound>();
+
+            fast_io::io::println(fast_io::out(), duration_second, "s");
+            fast_io::io::println(fast_io::out(), "size@ ", nfl.size(), "bytes");
+            fast_io::io::println(fast_io::out(), "speed@ ", nfl.size() / 1000.0 / 1000.0 / duration_second, "mb/s");
+            fast_io::io::println(fast_io::out(), "");
+        }
+        std::system("pause");
+    }
+}