hdu 1005 Number Sequence

 

//打表找规律

#include<stdio.h>
int main(void)
{
    int arr[1000]={0,1,1};
    int i,a,b,n;
    while(scanf("%d%d%d",&a,&b,&n),a||b||n)
    {
        for(i=3;i<1000;i++)
        {
            arr[i]=(a*arr[i-1]+b*arr[i-2])%7;
            if(arr[i]==1&&arr[i-1]==1)
                break;
        }
        n=n%(i-2);
        arr[0]=arr[i-2];
        printf("%d\n",arr[n]);
    }
    return 0;
}