size(200,200);
background(255);

int y = 80; // vertical location of each line //
int x = 50; // initial horizontal location for first line //
int spacing = 10; // how far apart is each line //
int len = 20; // length of eack line //
int endLegs = 150;

// Legs //
stroke(0);
while (x <= endLegs){
  line(x,y,x,y+len);
  x=y + spacing;
}