Problems > Sequence g=6a+5b (g0=0,g1=1)

Sequence g=6a+5b (g0=0,g1=1)

Difficulty: 1700 4000 ms 128 MB

math matrix-exponentiation

The sequence has g(0)=0, g(1)=1 and g(n)=6g(n−1)+5g(n−2). Print g(N) modulo 109+7.

Input: one integer N.

Output: g(N) mod 109+7.

Constraints:

  • 0 ≤ N ≤ 1018

Sample Tests

Input 1
5
Output 1
1861
Input 2
0
Output 2
0
Input 3
1
Output 3
1

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