Простые числа

#include <bits/stdc++.h>

using namespace std;

const int N = 3e5 + 3;

bool isPrime(int x) {
    if (x < 2) return 0;
    int sq = sqrt(x);
    for (int i = 2; i <= sq; i++) {
        if (x % i == 0) {
            return false;
        }
    }
    return true;
}

int pr[N];

int main(){

    for (int i = 2; i < N; i++) {
        if (pr[i] == 0) {
            if (1ll * i * i >= N) continue;
            for (int j = i * i; j < N; j += i) {
                pr[j] = 1;
            }
        }
    }

    int left, right;
    cin >> left >> right;

    int cnt = 0;
    for (int i = left; i <= right; i++) {
        if (pr[i] == 0) {
            cout << i << endl;
            cnt++;
        }
    }

    if (cnt == 0) {
        cout << "Absent" << endl;
    }
}