#ANTP. Mr. Ant & His Problem
Mr. Ant & His Problem
Mr. Ant has 3 boxes and the infinite number of marbles. Now he wants to know the number of ways he can put marbles in these three boxes when the following conditions hold.
- Each box must contain at least 1 marble.
- The summation of marbles of the 3 boxes must be in between X and Y inclusive.
Now you are given X and Y. You have to find the number of ways Mr. Ant can put marbles in the 3 boxes.
Input
Input starts with an integer T, denoting the number of test cases. Each test case contains two integers X and Y.
Constraints
1 ≤ T ≤ 1000000
1 ≤ X ≤ Y ≤ 1000000
Output
For each test case, print the required answer modulo 1000000007.
Example
Input: 1 4 5</p>Output: 9
Explanation for the first test case
| 1 | 1 | 2 |
Way 01
| 1 | 1 | 3 |
Way 02
| 1 | 2 | 1 |
Way 03
| 1 | 3 | 1 |
Way 04
| 2 | 1 | 1 |
Way 05
| 3 | 1 | 1 |
Way 06
| 1 | 2 | 2 |
Way 07
| 2 | 1 | 2 |
Way 08
| 2 | 2 | 1 |
Way 09
Note: use faster i/o method.
Problem Setter: Md Abdul Alim, Dept. of Computer Science, Bangladesh University of Business & Technology