HDOJ1013【Digital Roots】

 Problem : 1013 ( Digital Roots )     Judge Status : Accepted
RunId : 5929064    Language : C    Author : qq1203456195
Code Render Status : Rendered By HDOJ C Code Render Version 0.01 Beta

#include <stdio.h>
#include <string.h>
char num[1010];
int main()
{
    int i,j,k;
    while (scanf("%s",num),num[0]!='0')
    {
        for (i=0,j=0;i<strlen(num);i++)
            j+=num[i]-'0';
        k=10;
        for (i=0;k>9;j=k)
        {
            k=0;
            while (j)
            {
                k+=j%10;
                j/=10;
            }
        }
        printf("%d\n",k);
    }
    return 1;
}