在网上搜来也不一定找的到,呵呵.
只要大家乐意,我们当然也愿意做这样的事.当然我们也要一定的支持率...
大家也可以直接把题目发上来,让我们做做.

支持了！
现有一道题！大家看看吧！不过是英文的！
Digital Roots

Background
The digital root of a positive integer is found by summing the digits of the integer. If the resulting value is a single digit then that digit is the digital root. If the resulting value contains two or more digits, those digits are summed and the process is repeated. This is continued as long as necessary to obtain a single digit.

For example, consider the positive integer 24. Adding the 2 and the 4 yields a value of 6. Since 6 is a single digit, 6 is the digital root of 24. Now consider the positive integer 39. Adding the 3 and the 9 yields 12. Since 12 is not a single digit, the process must be repeated. Adding the 1 and the 2 yeilds 3, a single digit and also the digital root of 39.

Input
The input file will contain a list of positive integers, one per line. The end of the input will be indicated by an integer value of zero.

Output
For each integer in the input, output its digital root on a separate line of the output.

Example
Input
24
39
0

Output
6
3
这是ACM题。