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.

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

Added by:David Gómez
Date:2010-12-04
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64
Resource:My Own

hide comments
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
2016-05-21 16:25:12
I mistakingly printed 1 for 0 0 case . -_- . costed me 3 WA!!
2016-05-13 11:02:39 SUBHAM SANGHAI
@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
2016-03-15 18:24:39
Interesting Problem
Learnt lot of new concepts and specially properties of Fibonacci Series
2016-02-26 12:45:54 Vmcode
@ abhi_vicky, thanks, got A.C 0.0
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
2016-02-24 13:12:19 minhthai
that negative modulo tho ( ͡° ͜ʖ ͡°)
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"
2015-12-08 15:59:13 Vmcode
how is it possible in c???
2015-09-14 07:36:45 MishThi
4 Days !! And victory.. :D
Learnt a lot through this question.
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