Question

Write a C++ program that creates a one dimensional array with of length 5 elements. Your
program should read an integer from the keyboard and test if it is prime. If the integer is
prime, the program should insert the integer into the 3rd index of the array�

Answer 1

#include <iostream>

using namespace std;

bool is_prime(int number) {
    if (number < 2) return false;
    if (number == 2) return true;
    if (number % 2 == 0) return false;
    for (int i = 3; (i * i) <= number; i += 2) {
        if (number % i == 0) return false;
    }
    return true;
}

int main() {
    int array[5];
    int num;
    cin >> num;
    if (is_prime(num)) {
        array[2] = num;
    }

    return 0;
}