在屏幕上开出三个窗口：









用“ ”和“ ”键选择左窗口或右窗口为当前活动窗口，从键盘输入字符，字符就会从当前活动窗口的最下行开始显示，同时也在下窗口显示。当一行字符显示满后（左右窗口一行显示20个字符，下窗口显示50个字符），窗口自动向上卷动一行，输入的字符仍显示于最低一行，窗口最高一行向上卷动后消失,按ESC键程序运行结束。

-On the screen to open three windows: the " "　and the " "　button to select the window left or right window for the current active window, from the keyboard input characters, characters from the current active window will be the most down beginning to show, as well as the next window . When the show after the expiry of his characters (about his window display 20 characters, under the window displays 50 characters), the window automatically scroll line up, enter the characters are still displayed in the lowest line, the maximum window scroll up after his disappearance, according to ESC Run the end of key procedures.