a)　　分别以左和右对齐方式输出整数，域宽为12；

b)　　以八进制、十进制、十六进制输入/输出整数；

c)　　实现浮点数的指数格式和定点格式的输入/输出，并指定精度，按实际情况进行调整，直到满意为止；

d)　　把字符串读入字符型数组变量中，从键盘输入，要求输入串的空格也全部读入，以回车换行符结束；

-a) to the left and right, respectively, the alignment of the output integer, the domain width is 12　b) in octal, decimal, hexadecimal, input/output integer　c) realization of fixed-point floating-point format and the format of the index of input/output and specify the precision, adjusted according to actual situation, until satisfied　d) to read into the character string array variable input from the keyboard, the space requirements and all of the input string read to the end of carriage return line feed