HDU 1021/ZOJ 2060 Fibonacci Again(数论&整除推导&位运算技巧)

Fibonacci Again

http://acm.hdu.edu.cn/showproblem.php?pid=1021

http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=2060

Time Limit: 2000/1000 MS (Java/Others)    

Memory Limit: 65536/32768 K (Java/Others)

There are another kind of Fibonacci numbers: F(0) = 7, F(1) = 11, F(n) = F(n-1) + F(n-2) (n>=2)

Input

Input consists of a sequence of lines, each containing an integer n. (n < 1,000,000)

Output

Print the word "yes" if 3 divide evenly into F(n).

Print the word "no" if not.

Sample Input

0

1

2

3

4

5

Sample Output

no

no

yes

no

no

no

规律同 NEFU 115。

完整代码：（用了下位运算技巧）

/*HDU: 0ms,220KB*/
/*ZOJ: 0ms,180KB*/

#include <cstdio>
using namespace std;

int main(void)
{
	int n;
	while (~scanf("%d", &n))
	{
		n &= 7;//大家可以算一下~
		printf("%s\n", n == 2 || n == 6 ? "yes" : "no");
	}
	return 0;
}