#include using namespace std; int countWays(int n) { if (n <= 0) { return 0; } else if (n == 1) { return 1; } else if (n == 2) { return 2; } else { return countWays(n - 1) + countWays(n - 2); } } int main() { int n; while (cin >> n) { cout << countWays(n) << endl; } return 0; }