백준 1978번 : 소수 찾기

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

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

int main() {
    int N, count = 0;
    cin >> N;
    
    vector<int> numbers(N);
    for (int i = 0; i < N; i++) {
        cin >> numbers[i];
    }

    for (int i = 0; i < N; i++) {
        if (isPrime(numbers[i])) {
            count++;
        }
    }

    cout << count << '\n';
}