#5703. CSES2185 质数倍数
0
CSES2185 质数倍数
Prime Multiples
You are given k distinct prime numbers a_1,a_2,\ldots,a_k and an integer n. Your task is to calculate how many of the first n positive integers are divisible by at least one of the given prime numbers.
Input
The first input line has two integers n and k. The second line has k prime numbers a_1,a_2,\ldots,a_k.
Output
Print one integer: the number integers within the interval 1,2,\ldots,n that are divisible by at least one of the prime numbers.
Constraints
^{18}$
Example
Input
20 2
2 5
Output
12
Explanation: the 12 numbers are 2,4,5,6,8,10,12,14,15,16,18,20.