Submission

Score: 100

User: RusticJoe26

Problemset: จำนวนเฉพาะ (2560)

Language: cpp

Time: 0.004 second

Submitted On: 2026-10-12 08:56:05

#include <iostream>
using namespace std;

int main(){
    int inp;
    cin >> inp;
    bool is_prime[inp];
    for(int i = 0; i < inp; i++) {
        is_prime[i] = true;
    }
    for (int p = 2; p * p <= inp; p++) {
        if (is_prime[p] == true) {
            
            // marking as false
            for (int i = p * p; i <= inp; i += p)
                is_prime[i] = false;
        }
    }
    for(int i = 2; i < inp; i++) {
        if(is_prime[i]) cout << i << endl;
    }
}