HDU 1005 Number Sequence

Number Sequence

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 136403    Accepted Submission(s): 33062

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<stdio.h>
int main()
{
__int64 a,b,n;
while(scanf("%I64d%I64d%I64d",&a,&b,&n)!=EOF&&(a||b||n))
{
__int64 c[105],i,k;
c[1]=1;c[2]=1;
for(i=3;i<100;i++)
{
c[i]=(a*c[i-1]+b*c[i-2])%7;
if(c[i]==1&&c[i-1]==1)
break;
}
i=i-2;
k=n%i;
if(k==0)
printf("%I64d\n",c[i]);
else
printf("%I64d\n",c[k]);
}
return 0;
}