#include <iostream>

using namespace std;

// sequence is 0, 1, 1, 2, 3, 5, 8, 13, ...
/*
int main() {
    int number;
    char contin = 'Y';

    while(toupper(contin) == 'Y') {
      cout << "Enter a number: ";
       cin >> number;
      cout << endl << "The prime number is: " << FindPrime(number) << endl;
      cout << endl << "Would you like to continue? (Y/N): ";
       cin >> contin;
    }
}
*/

int fib (int i) {
  int pred, result, temp;

  pred = 1;
  result = 0;

  while (i > 0) {
    temp = pred + result;
    result = pred;
    pred = temp;
    i = i-1;
  }
  return(result);
}

int main () {
char contin = 'Y';

while(toupper(contin) == 'Y')

  int n;
  cout << "Enter a natural number: ";
  cin >> n;
  while (n < 0) {
    cout << "Please re-enter: ";
    cin >> n;
  }
  cout << "fib(" << n << ") = " << fib(n) << endl;
  return(0);
}