说明：  C语言教程. 一、概述上 下. 二、变量和常量. 三、运算符. 四、表达式和语句. 五、编写第一个C语言程序. 六、条件语句. 七、循环语句和循环控制. 八、数组. 九、多维数组
(C language tutorial. I. Overview and down Second, variables and constants. Three operators. Fourth, expressions and statements. V. Write the first C language program six, conditional statements. Seven, Loop and loop control. eight, array nine, multidimensional arrays)