Number Sequence
Problem Description 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).
Input 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.
Output For each test case, print the value of f(n) on a single line.
Sample Input 1 1 3 1 2 10 0 0 0
Sample Output 2 5
源代码：
#include<iostream> using namespace std; int f(int n, int A, int B){ if(n==1 || n==2)return 1; else return (A * f(n-1, A, B) + B * f(n-2, A, B))%7; } int main(){ int A=5,B=3,n; while(cin>>A>>B>>n && A||B||n ){ cout<<f(n%48,A,B)<<endl; } return 0; }问题注意：结果是有规律的，然而我也不知道为什么是48
