Mancunian And Naughty Numbers

3.3

44 votes
Mathematics, Easy, Number Theory, Factorization
Problem

Mancunian, our favourite football fan, is a die-hard supporter of Manchester United Football Club. Being so, he is desperate to attend the grand unveiling of Jose Mourinho as the next manager of the club. But, his arch-nemesis Liverbird (who is a Liverpool fan) wants him to fail. Knowing that Mancunian is weak at mathematics, he has given him a problem to solve before the ceremony. Can you help Mancunian do it and thwart the evil plans of Liverbird?

A naughty number is one whose number of distinct prime factors is equal to the number of digits in its decimal representation. The number 1 is considered a naughty number.

Given Q queries, each query specifying two integers a and b, find the number of naughty numbers lying between a and b (both included).

Input format

The first line contains an integer Q denoting the number of queries.
Each of the next Q lines consists of two integers a and b denoting the range for this query.

Output format

Print Q lines. The ith line contains the answer for the ith query.

Constraints

  • 1Q50,000
  • 1ab100,000
Time Limit: 2
Memory Limit: 256
Source Limit:
Explanation

In the range 1-10, all numbers except 6 are naughty numbers.
In the range 55-59, the naughty numbers are 55, 56, 57 and 58.
In the range 100-105, only 102 and 105 are naughty numbers.

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