九余數定理

一個數對九取余后的結果稱為九余數。

一個數的各位數字之和想加后得到的<10的數字稱為這個數的九余數（如果相加結果大于9，則繼續各位相加）

Digital Roots

Time Limit: 2000/1000 MS (Java/Others)????Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 87400????Accepted Submission(s): 27256


Problem Description 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.

Sample Input 24 39 0
Sample Output 6 3
Source Greater New York 2000
#include<stdio.h> #include<string.h> int main() { char num[1000]; int len,sum,i; while(scanf("%s",&num)!=EOF)//這里為什么要字符串輸入呢？原因是因為有一個測試數據很大，int類型肯定過不了，所以在這坑點我wa好幾次{ len=strlen(num); if(len==1 && num[0]=='0') return 0; for(sum=0,i=0;i<len;i++) { sum=sum+num[i]-'0'; } printf("%d\n",sum%9?sum%9:9); } return 0; }

總結

以上是生活随笔為你收集整理的九余定理（hdu1013）的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。