prime numbers code code example

Example 1: prime chec kin c

int isPrime(long long number) {

	if (number == 0 || number == 1 || (number % 2 == 0 && number > 2)) {
		return 0;
	}

	else {
		for (long long i=3; i <= (long long)sqrt(number)+1; i++) {
			if (number % i == 0) {
				return 0;
			}
		}
		return 1;
	}
}

Example 2: program to know if a number is prime

#include<bits/stdc++.h>
using namespace std;
bool Is_Prime(long long x){
	if(x%2==0)return false;
	for(int i=3;i*i<=x;i+=2)
		if(x%i==0)return false;
	return true;
}
int main(){
	long long x;
	cin>>x;
	if(Is_Prime(x))cout<<"Is Prime";
	else cout<<"Is not Prime";
}

Example 3: prime number c

#include <stdio.h>
int main()
{
   int i, num, p = 0;
   printf("Please enter a number: \n");
   scanf("%d", &num);
   for(i=1; i<=num; i++)
   {
      if(num%i==0)
      {
         p++;
      }
   }
   if(p==2)
   {
      printf("Entered number is %d "\
             "and it is a prime number.",num);
   }
   else
   {
      printf("Entered number is %d "\
             "and it is not a prime number.",num);
   }
}

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Cpp Example