hdoj-1005-Number Sequence

计算结果存在循环，每48一轮循环

#include <iostream> 
#include <algorithm>
using namespace std;
int arr[50];
int main()
{
    int a, b, n;
    while (cin>>a>>b>>n, a+b+n) {
        arr[1] = 1;
        arr[2] = 1;
        for (int i=3; i<=48; i++) {
            arr[i] = (a*arr[i-1] + b*arr[i-2]) % 7;
        }
        cout<<arr[n%48]<<endl;
    }
    return 0;
}