## 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 harsh gupta: 2016-06-11 22:40:31 can anyone post a tricky test case which involves negative modulo ?? lynx_: 2016-05-24 11:50:04 Used Dijkstra's formula...with memorization... F(2*n-1)=F(n)*F(n)+F(n-1)*F(n-1) F(2*n)=(2*F(n-1)+F(n))*F(n).. 0.02 secs..AC piyushhh: 2016-05-21 16:25:12 I mistakingly printed 1 for 0 0 case . -_- . costed me 3 WA!! SUBHAM SANGHAI: 2016-05-13 11:02:39 @buttman , Though given n<=m .But you are taking mod with 10^9+7;So there might be a problem of a negative mod.Take this case ,suppose (N!)=(10^9+6) and (M)!=(10^9)+8, (M!)%mod=1 and (N!)%mod=(10^9)+6; so here (M!)-(N!) <0 Last edit: 2016-05-13 11:05:05 buttman: 2016-05-09 11:18:54 Last edit: 2016-05-14 05:32:30 harshitdd120: 2016-03-15 18:24:39 Interesting Problem Learnt lot of new concepts and specially properties of Fibonacci Series Vmcode: 2016-02-26 12:45:54 @ abhi_vicky, thanks, got A.C 0.0 abhi_vicky: 2016-02-24 21:16:50 It is possible in C #Vmcode by using matrix exponantion and sum of fibonacci series!!!!AC in 0.01s minhthai: 2016-02-24 13:12:19 that negative modulo tho ( ͡° ͜ʖ ͡°) buvaneish: 2016-01-10 16:59:05 i am getting nzec error by pyth 2.7 please help me out it says"maximum recursion depth reached"