orm-label">请选择一个 Linux ELF 格式的可执行文件：</label>
                <input id="file1" type="file" name="file" class="form-control-file">
            </div>
            <div class="form-group">
                <label for="stage" class="form-label">请选择解的小题：</label>
                <select id="stage" name="stage" class="form-control">
                    <option value="1"{% if selected == 1 %} selected{% endif %}>1: LD_PRELOAD</option>
                    <option value="2"{