Source code in the processing programming language

int n = 18;
String f1 = "1";
String f2 = "0";
String f3;


void setup(){
  size(600,600);
  background(255);
  translate(10, 10);
  createSeries();
}

void createSeries(){
  for(int i=0; i<n; i++){
    f3 = f2+f1;
    f1 = f2;
    f2 = f3;
  }
  drawFractal();
}

void drawFractal(){
  char[] a = f3.toCharArray();
  for(int i=0; i<a.length; i++){
    if(a[i]=='0'){
      if(i%2==0){
        rotate(PI/2);
      }
      else{
        rotate(-PI/2);
      }
    }
    line(0,0,2,0);
    translate(2,0);
  }
}