Fibonacci Prefix Sum
Print F(0)+F(1)+…+F(N) modulo 109+7, where F(0)=0, F(1)=1.
Input: one integer N.
Output: the prefix sum mod 109+7.
Constraints:
- 0 ≤ N ≤ 1018
Sample Tests
Input 1
5
Output 1
12
Input 2
0
Output 2
0
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