程序接收用户键入的一行字符（字符长度不大于80个，以回车结束），并把字符，数字，其它字符分类计数，然后将结果存入以Letter，Digit，Other为名的存储单元中。-Procedures for receiving a user types a line of characters (characters in the length of not more than 80 to enter the end), and put characters, numbers, other charac