check prime cpp code example
Example 1: c++ find prime numbers
using namespace std;
int main()
{
int n, i;
bool isPrime = true;
cout << "Enter a positive integer: ";
cin >> n;
for(i = 2; i <= n / 2; ++i)
{
if(n % i == 0)
{
isPrime = false;
break;
}
}
if (isPrime)
cout << "This is a prime number";
else
cout << "This is not a prime number";
return 0;
}
Example 2: check prime in c++
using namespace std;
bool checkPrime(int number){
for(int i=2; i<=sqrt(number); i++){
if(number%i==0){
return false;
}
}
return true;
}
Example 3: program to know if a number is prime
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 4: check prime number c++
using namespace std;
int main() {
int i, n;
bool isPrime = true;
cout << "Enter a positive integer: ";
cin >> n;
// 0 and 1 are not prime numbers
if (n == 0 || n == 1) {
isPrime = false;
}
else {
for (i = 2; i <= n / 2; ++i) {
if (n % i == 0) {
isPrime = false;
break;
}
}
}
if (isPrime)
cout << n << " is a prime number";
else
cout << n << " is not a prime number";
return 0;
}