Any natural number greater than 1 that can only be divided by 1 is referred to as a prime number.
eg: 2,3,5,7,11 these are the few examples of prime numbers, that can be divided by either 1 or by itself.
Example Program to find the Primer Number in C
#include <stdio.h>
int main() {
int n, i, isPrimeNumber = 0;
printf("Enter a positive integer Number: ");
scanf("%d", &n);
// 0 and 1 are not prime numbers
// change isPrimeNumber to 1 for non-prime number
if (n == 0 || n == 1){
isPrimeNumber = 1;
}
for (i = 2; i <= n / 2; ++i) {
// if n is divisible by i, then n is not prime
// change isPrimeNumber to 1 for non-prime number
if (n % i == 0) {
isPrimeNumber = 1;
break;
}
}
// isPrimeNumber is 0 for prime numbers
if (isPrimeNumber == 0)
printf("%d is a prime number.", n);
else
printf("%d is not a prime number.", n);
return 0;
}
Check if 11 is a primer number.
Check if 9 is a primer number.
