#include <iostream> using namespace std; int main() { int k; cin >> k; if (k == 1 || k == 2) { cout << 1 << endl; return 0; } int a = 1, b = 1; for (int i = 3; i <= k; i++) { int temp = a + b; a = b; b = temp; } cout << b << endl; return 0; }