DHOJ1005 HDU1005 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
   
   
   
   

#include using namespace std; #define M 52 int main() { int f[10000]; int a,b,n; while(cin>>a>>b>>n&&(a||b||n) ) { f[1]=1; f[2]=1; a=a%7; b=b%7; for(int i=3;i<=M;i++) { f[i]=(a*f[i-1]+b*f[i-2]) % 7; if(f[i-1]==f[3]&&f[i]==f[4]&&i>4) break; } int t=i-4; if(n<4) cout<