Sequence r=3a+2b (r0=0,r1=1)
The sequence has r(0)=0, r(1)=1 and r(n)=3r(n−1)+2r(n−2). Print r(N) modulo 109+7.
Input: one integer N.
Output: r(N) mod 109+7.
Constraints:
- 0 ≤ N ≤ 1018
Sample Tests
Input 1
5
Output 1
139
Input 2
0
Output 2
0
Input 3
1
Output 3
1
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