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Quiz 2 sample

Sample question for in-class quiz on April 11th (Wednesday)

Study the following code. It should meet the following specification, but it does not. Your task is to rewrite the code so that it is correct.

The function is_prime determines whether its input is a prime number. Recall that a prime number is defined as those integers (greater than 1) that are divisible by only themselves and 1 (of course 1 divides every integer). So 7 is prime because the only numbers that divide 7 are 7 itself and 1. But 9 is not prime because 9 is divisible by 3.

Here is a program that has the is_prime function and a main function. There are several errors in both functions. Rewrite the code so it is correct.

include <iostream>
using namespace std;

int main()
{
    char c = 'Y';
    while(c == 'Y');
    {
        cout << Enter a number: << endl;
        cin >> n;

        bool p = is_prime(n)
        if(p)
        {
             cout << n << " is not prime." << endl;
        }
        else
        {
             cout << n << " is prime." << endl;
        }

        cout << "Do it again? Enter Y or N:"
        cin >> c;
    }
    return 0;
}

void is_prime()
{
    int n;
    for(int i = 1; i < n; i++)
    {
        if(i % n == 0)
        {
            prime = false;
        }
        else
        {
            prime = true;
        }
    }
    return prime;
}