这是一个打字计时练习的程序,在缓冲区中预放了一些字母,运行时,可按照屏幕上 显示的字母输入练习,每输入完一行按回车键后,可显示出练习输入的时间.-This a time to practice typing procedures, the pre-release buffer some letters, operation, in accordance with the screen displayed on the alphanumeric input practice every impor