fork download 
  1. #include <iostream>
  2.  
  3. typedef long long ll;
  4.  
  5. const ll mod = ll(1e9)+7;
  6.  
  7. int main() {
  8. 	ll a = 1, b = 0, n;
  9.  
  10. 	std::cin >> n;
  11.  
  12. 	for (ll i = 0; i < n; ++i) {
  13. 		ll new_a = a * 3 + b;
  14. 		ll new_b = b * 3 + a;
  15. 		a = new_a;
  16. 		b = new_b;
  17. 	}
  18.  
  19. 	std::cout << a;
  20.  
  21. 	return 0;
  22. }
Success #stdin #stdout 0s 4376KB
comments (?)
stdin 
10
stdout 
524800
https://ideone.com/q2ikIz
language:
C++14 (gcc 8.3)
created:
7 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!