Submission

Score: 80

User: s0m30n3

Problemset: จำนวนเฉพาะ (2560)

Language: cpp

Time: 0.002 second

Submitted On: 2025-09-26 21:20:40

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int n;
    cin >> n;
    vector<int> arr(n+1, 0);

    for (int i = 2; i * i <= n; i++) {
        if (arr[i] == 0) { // i เป็นจำนวนเฉพาะ
            for (int j = i * i; j <= n; j += i) {
                arr[j] = 1;
            }
        }
    }

    for (int i = 2; i <= n; i++) {
        if (arr[i] == 0)
            cout << i << '\n';
    }
}