Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

// Prog: snowflake.cpp // Draw turtle graphics for the Lindenmayer system with // production F -> F-F++F-F, initial word F++F++F and // rotation angle 60 degrees. #include #include // POST: the word w_i^F is drawn void f (const unsigned int i) { if (i == 0) ifm::forward(); // F else { f(i-1); // w_{i-1}^F ifm::right(60); // - f(i-1); // w_{i-1}^F ifm::left(120); // ++ f(i-1); // w_{i-1}^F ifm::right(60); // - f(i-1); // w_{i-1}^F } } int main () { std::cout << "Number of iterations =? "; unsigned int n; std::cin >> n; // draw w_n = w_n^F++w_n^F++w_n^F f(n); // w_n^F ifm::left(120); // ++ f(n); // w_n^F ifm::left(120); // ++ f(n); // w_n^F return 0; }