PIPI want to divide the integers in [A, B] into some sets.
Initially,every integer is in its own set. If two integers i, j belongs to two sets si,sj, but i and j are both multiple of a prime p which is no less than P,you should union si, sj .
Calculate the number of sets in the end.

3 integers , A, B, P, (1 ≤ A ≤ B ≤ 10¹², B ≤ A + 10⁶, 2 ≤ P ≤ B)

1 interger, the number of sets in the end.

困难 数学 图