#include using namespace std; typedef long long int lli; #define M 200000 bool marked[M]; bool isPrime(int n) { if (n < 2) return false; if (n == 2) return true; if (n % 2 == 0) return false; return marked[n] == false; } void sieve(int n) { for (int i = 3; i * i <= n; i += 2) { if (marked[i] == false) // i is a prime { for (int j = i * i; j <= n; j += i + i) { marked[j] = true; } } } } int main() { sieve(200000); vectorprime; for(lli i=0; i<200000; i++) { if(isPrime(i)) prime.push_back(i); } //for(lli i=0; in) { //cout<