Not Prime no in c pgm

#include 

#include 

#include 

int fermatTest (int n)

 {

  int a;

  a = rand() % n;

  cout << "Trying with " << a << endl;

  return (a == (int(pow(a,n)) % n));

}

int main ()

 {

  int n, i;

  cout << "Enter a natural number: ";

  cin >> n;

  cout << "How many trials?: ";

  cin >> i;

  srand(n*i);

  while (i > 0) 

{

    if (fermatTest(n)) 

{

      i = i-1;

    } 

    else 

{

      cout << "The number " << n << " is definitely not prime." << endl;

      return(0);

    }

  }

  cout << "The number " << n << " is probably prime." << endl;

  return(0);

}