Submission

Score: 80

User: thereal_zenitsu10

Problemset: จำนวนเฉพาะ (2560)

Language: cpp

Time: 0.003 second

Submitted On: 2026-10-15 13:54:38

#include <iostream>
#include <vector>

using namespace std;

const int N = 7000000;
bool isComposite[N];
vector<int>prime;

void sieve(int n) {
    isComposite[0] = isComposite[1] = true;

    for (int i = 2; i * i <= n; i++) {
        if (!isComposite[i]) {
            for (int j = i * i; j <= n; j += i) {
                isComposite[j] = true;
            }
        }
    }
}

void countprime(int n){
    for(int i=1;i<=n;i++){
        if(!isComposite[i]){
            prime.push_back(i);
        }
    }
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin>>n;
    sieve(n);
    countprime(n);
    for(auto i : prime){
        cout<<i<<'\n';
    }
    return 0;
}