Beautiful Sequence

4.4

5 votes
Mathematics, Hard, Modular arithmetic, Number Theory
Problem

A sequence is beautiful if the number of times each number appears in that sequence is divisible by 5. For example, (1,1,1,1,1,3,3,3,3,3) is beautiful while (1,1,1,1,1,3) is not.

You are given Q queries, each comprises two integers N,M. You must count the number of beautiful sequences of N integers where each element ranges from 1 to M. (Two sequences are different if there exists a position where elements in two sequences are different.)

Input format

  • First line: Integer Q denoting the number of queries
  • Each of the Q following lines: Two space-separated integers N,M

Output format

  • For each query, print the answer to the modulo 5011 in a single line.

Constraints

1Q1000

1N1018

1M1018

Time Limit: 2
Memory Limit: 512
Source Limit:
Explanation

In the first query, there is only one beautiful sequence: (1,1,1,1,1).

In the second query, there are two beautiful sequences: (1,1,1,1,1),(2,2,2,2,2).

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