C++ question on prime numbers.
- by user278330
Hello. I am trying to make a program that determines if the number is prime or composite. I have gotten thus far. Could you give me any ideas so that it will work? All primes will , however, because composites have values that are both r0 and r==0, they will always be classified as prime. How can I fix this?
int main()
{
int pNumber, limit, x, r;
limit = 0;
x = 2;
cout << "Please enter any positive integer: " ;
cin >> pNumber;
if (pNumber < 0)
{
cout << "Invalid. Negative Number. " << endl;
return 0;
}
else if (pNumber == 0)
{
cout << "Invalid. Zero has an infinite number of divisors, and therefore neither composite nor prime." << endl;
return 0;
}
else if (pNumber == 1)
{
cout << "Valid. However, one is neither prime nor composite" << endl;
return 0;
}
else
{
while (limit < pNumber)
{
r = pNumber % x;
x++;
limit++;
}
if (r == 0)
cout << "Your number is composite" << endl;
else
cout << "Your number is prime" << endl;
}
return 0;
}
