## FIBOSUM - Fibonacci Sum

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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.

### Input

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.

### Output

For each test case you have to output a single line containing the answer for the task.

### Example

```Input:
3
0 3
3 5
10 19

Output:
4
10
10857```

### Constraints

• T <= 1000
• 0 <= N <= M <= 109 sandeep_123: 2017-12-14 21:46:06 Matrix exponentiation and f(1)+f(2)+f(3)+... + f(n) = f(n+2)-1 did this :D !! 82nd AC sirjan13: 2017-10-08 19:06:09 Matrix Expo :) babur: 2017-08-23 14:38:43 AC after 1 wa....take care of negative modulus.. swarup03: 2017-07-14 08:55:24 Ac in one go :) Didn't use Matrix Exponention, Dijkstra's formula was good enough. And yes negative mod must be taken into account. Thanks @sagnik_66 for the hint sandeep_4141: 2017-06-23 10:31:35 learn something new !! Matrix exponentiation !! care about mod !! anurag44: 2017-06-14 22:46:36 use long long !! Cost me 3WA's rakcode1998: 2017-06-11 14:07:35 Why will it ever be negative? @sagnik_66 Last edit: 2017-06-11 14:07:57 sagnik_66: 2017-06-09 18:23:45 Take care about the negative answers. Just add 1000000007. Matrix Exponentiation gives answer in 0.0 secs anurag_333: 2017-05-30 13:19:40 @vineetpratik can you show me your dijkshra code?? how did you memorized the fibonacci no. since constrains is 10e9! and we cant save this much in memory thakur13: 2017-05-05 11:34:57 Jbardast Problem