FIBOSUM - Fibonacci Sum
The fibonacci sequence is defined by the following relation:
- F(0) = 0
- F(1) = 1
- F(N) = F(N - 1) + F(N - 2), N >= 2
Your task is very simple. Given two non-negative integers N and M, you have to calculate the sum (F(N) + F(N + 1) + ... + F(M)) mod 1000000007.
The first line contains an integer T (the number of test cases). Then, T lines follow. Each test case consists of a single line with two non-negative integers N and M.
For each test case you have to output a single line containing the answer for the task.
Input: 3 0 3 3 5 10 19 Output: 4 10 10857
- T <= 1000
- 0 <= N <= M <= 109
can't believe that it is accepted in 1st go.. yepppeeeeeeeeeeeeeeee
Great problem! I am content with 0.02 but I highly recommend reading the forum thread by Rafael Perrella. I guarantee you will learn something. Definitely never knew about that secret of the Fibonacci numbers.
hi,all! I am stuck here and I need help! Thanks so much in advance.
Alexandre Henrique Afonso Campos:
I have a solution that works for all listed cases here and in the forums previously mentioned here in the comments, including trick cases. Still getting WA.
I don't know any link where it is discussed. But you can start a thread and post the link here, then we can discuss it there.
@Rafael Perrella : Thank you for answering my question & congratulations for solving this problem in 0.00s. :)