Input from the keyboard a decimal digit string ends with a carriage return (no more than 20) requirements: 1) according to the ASCII value of the descending order according to the number in the string of ASCII value maximum and minimum of two Numbers; 2) displayed in decimal Numbers in all digital and; 3) displayed in decimal Numbers in maximum number and the smallest number of the product; 4) to deal with the Numbers, make each character in the string appears only once; 5) data of the input and output of the results are necessary, and suggest an exclusive line; 6) to use to the subroutine,