[Leetcode 204] Count Primes

Title Link: count-primes

Description:

Count the number of prime numbers less than a non-negative number, n

public class Solution {public int countprimes (int n) {if (n <= 2) return 0; List<integer> primes = new arraylist<integer> ();p Rimes.add (2); for (int i = 3; i < n; i + = 2) {int sqrt_i = (int) MATH.SQRT (i); for (int j = 0; I% primes.get (j) = 0; j + +) {if (Primes.get (j) > Sqrt_i) {primes.add (i); break;}}} return Primes.size ();    }}

[Leetcode 204] Count Primes