java高级编程教案，PPT的，一共九章，适合高级程序员学习-java advanced programming lesson plans, PPT, and a total of nine chapters, suitable for high-level programmers to learn

随机产生五个、七个或九个字母，用户可以选择游戏等级猜字母(Randomly generated five, seven or nine letters, the user can choose the game level, guess the alphabets.)