DMOPC '19 Contest 2 P4 - A Greedy Problem

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Points: 15 (partial)
Time limit: 0.1s
Java 0.6s
PyPy 2 0.3s
PyPy 3 0.3s
Memory limit: 128M

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Problem type

Jack is doing a programming contest. There are N problems in this contest and the contest will last a total of T minutes. The i-th problem will take Jack exactly ti minutes to solve. Having an aversion to certain problem types such as dynamic programming, Jack wonders how many subsets of problems he can solve within qi minutes if he decides that he definitely wants to solve problem ai and problem bi. More formally, Jack wants to determine the number of subsets of problems that contain problem ai and problem bi whose sum of solve times is less than or equal to qi. Since this number may be very large, output it modulo 109+7. Two subsets are different if there is a problem in one of the subsets that does not appear in the other subset.

Help Jack answer a total of Q of these queries.

Constraints

In all subtasks,
2N,T,Q2000
1ti,qiT
1ai,biN
aibi

Subtask 1 [20%]

N,T100

Subtask 2 [20%]

Q10

Subtask 3 [60%]

No additional constraints.

Input Specification

The first line contains three space-separated integers, N T Q.
The next line contains N space-separated integers, t1,t2,,tN.
The next Q lines contain three space-separated integers, ai bi qi.

Output Specification

Output Q lines. The i-th line should contain the answer to the i-th query.

Sample Input

Copy
3 90 2
20 30 40
1 2 50
1 3 90

Sample Output

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1
2

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