2. Program to check whether a number is prime.
1. Program to check whether a number is prime.
#include <iostream.h>
#include <conio.h>
int main() {
int n, i, isPrime = 1;
cout << "Enter a positive integer: ";
cin >> n;
// 0 and 1 are not prime numbers
if (n == 0 || n == 1) {
isPrime = 0;
} else {
for (i = 2; i <= n/2; ++i) {
if (n % i == 0) {
isPrime = 0;
break;
}
}
}
if (isPrime)
cout << n << " is a prime number.\n";
else
cout << n << " is not a prime number.\n";
getch();
return 0;
}