diff --git a/demo.cpp b/demo.cpp
new file mode 100644
index 0000000..24b7f55
--- /dev/null
+++ b/demo.cpp
@@ -0,0 +1,47 @@
+#include <iostream>
+//#include <io.h>     //_setmode()
+//#include <fcntl.h>  //
+#include <string>
+#include "windows.h"
+
+// source link: https://github.com/microsoft/terminal/issues/15380
+
+int main()
+{
+    using namespace std;
+    auto out_cp = GetConsoleOutputCP(); // To restore output code page at exit.
+    auto inp_cp = GetConsoleCP();       // To restore input  code page at exit.
+    SetConsoleOutputCP(CP_UTF8); // Set console output code page to UTF-8 encoding.
+    SetConsoleCP(CP_UTF8);       // Set console input  code page to UTF-8 encoding.
+
+    cout << "Test: あああ🙂🙂🙂日本👌中文👍Кириллица" << endl; // Make sure you save your project file with 65001(UTF-8) encoding.
+
+    // Update: Windows console UTF-8 input has been fixed in #14745.
+    auto utf8 = string{};
+    cout << "Enter text: ";
+    cin >> utf8;
+    cout << "UTF-8 text: " << utf8 << endl;
+
+    // Outdated.
+    //auto wide = wstring{};
+    //auto utf8 = string{};
+    //cout << "Enter text: ";
+    //// stdin should be configured in order to receive wchar_t (you can't receive in UTF-8 encoding on Windows yet)
+    //_setmode(_fileno(stdin), _O_U16TEXT);
+    //wcin >> wide;
+    //
+    //// Optional: stdout should be configured to output wide strings
+    //_setmode(_fileno(stdout), _O_U16TEXT);
+    //wcout << L"Wide  text: " << wide << endl;
+    //_setmode(_fileno(stdout), _O_TEXT); // Restore to UTF-8.
+    //
+    //// or convert wide-string to UTF-8 string before output it
+    //utf8.resize(wide.size() * 3); // Resize utf8 buffer for the worst case.
+    //auto size = WideCharToMultiByte(CP_UTF8, 0, wide.data(), (DWORD)wide.size(), utf8.data(), (DWORD)utf8.size(), 0, 0);
+    //utf8.resize(size);
+    //cout << "UTF-8 text: " << utf8 << endl;
+
+    SetConsoleOutputCP(out_cp); // Restore original system code pages.
+    SetConsoleCP(inp_cp);       //
+    return 0;
+}