Number Sequence

题目描述

A number sequence is defined as follows:
 f(1) = 1, f(2) = 1, f(n) = (A * f(n - 1) + B * f(n - 2)) mod 7.
Given A, B, and n, you are to calculate the value of f(n).

输入

The input consists of multiple test cases. Each test case contains 3 integers A, B and n on a single line (1 <= A, B <= 1000, 1 <= n <= 100,000,000). Three zeros signal the end of input and this test case is not to be processed.

输出

For each test case, print the value of f(n) on a single line.

示例输入

1 1 31 2 100 0 0

示例输出

25

#include <iostream>  
#include <algorithm>  
using namespace std;  
long long int f[100000001];  
int main()  
{  
    int n,m,k,a,b,i;  
    f[1]=1;f[2]=1;  
    while(cin>>a>>b>>n&&a!=0||b!=0||n!=0)  
    {  
            for(i=3;i<=n;i++)  
    {  
        f[i]=((f[i-1]*a%7)+(f[i-2]*b%7));  
    }  
    cout<<f[n]<<endl;  
  
    }  
}