Submission

Score: 100

User: TTkoiep

Problemset: จำนวนเฉพาะ (2560)

Language: cpp

Time: 0.002 second

Submitted On: 2025-10-18 22:46:31

#include <iostream>
#include <cstring>

using namespace std;
void sieve(int n){

    bool primenum[n+1];
    memset(primenum, true, sizeof(primenum));
    for(int i = 2; i*i < n; i++){
        if(primenum[i] == true){
            for(int j = i*i; j < n; j+=i){
                primenum[j] = false;
            }
        }
    }

    for(int i = 2; i < n; i++){
        if(primenum[i]){
            cout << i <<  endl;
        }
    }

}

int main(){

    int i; cin >> i;
    if(i < 1 || i > 100) return 0;
    sieve(i);


    return 0;
}