斐波那契
Time Limit: 3 s
Memory Limit: 256 MB
Submission:167
AC:12
Score:99.35
Description
斐波那契数列的定义如下:
\begin{cases}
F(x) = 0 \qquad (x = 0)\\
F(x) = 1 \qquad (x = 1)\\
F(x) = F(n - 1) + F(n - 2) \quad (x \ge 2)
\end{cases}
即F=[1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, ...]
给出n,求(\sum{ F^2(n)+2*F(n-1)*F(n)}) \pmod{10^9+7}
Input
输入一个数n(1 \leq n \leq 10^{18})
Output
输出结果
Samples
input
2
output
4
Author