C Program to Check Whether a Number is Prime or Not.
2 ) //C Program to Check Whether a Number is Prime or Not #include <stdio.h> #include <stdbool.h> bool isPrime(int number) { if (number <= 1) { return false; // 0 and 1 are not prime numbers } for (int i = 2; i * i <= number; i++) { if (number % i == 0) { return false; // If the number is divisible by any integer from 2 to sqrt(number), it's not prime. } } return true; // If no divisors were found, the number is prime. } int main() { int num; printf("Enter a number: "); scanf("%d", &num); if (isPrime(num)) { printf("%d is a prime number.\n", num); } else { printf("%d is not a prime number.\n", num); } return 0; }