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IX Olimpiada Informatyczna 2001/2002

Task: lic
Author: Wojciech Guzicki
B-Smooth Numbers

III stage contest  

Let B be a positive integer. A natural number n is called B-smooth, if in its factorisation into primes there is no prime factor greater then B. We may say equivalently that a number n is called B-smooth, if it may be represented as a product of positive integers less then or equal to B.


Write a program which:
  • reads from the text file lic.in three positive integers n, m and B,
  • determines the number of all B-smooth numbers in the interval [n,n+m] (inclusive),
  • writes the result to the text file lic.out.


In the first line of the text file lic.in there are three integers n, m and B, separated by single spaces, 1<=n<=2 000 000 000, 1<=m<=100 000 000, 1<=B<=1 000 000.


Your program should write one integer in the first line of the text file lic.out. It should be the determined number of B-smooth numbers.


For the following input file lic.in:
30 10 5
the correct answer is in the following output file lic.out:

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