How to stop turtles when all patches have been colored?

Question

How to stop turtles when all patches have been colored in Netlogo?

When the turtles have covered the world in patches, I would like the turtles to stop on the last one so that I can record the amount of ticks it took.

Here is my code so far:

turtles-own [time-since-last-found]

---

to setup
  ca
  ask n-of num-clusters patches [
      ask n-of 20 patches in-radius 5 [
          set pcolor red
      ]
  ]
  crt 1 [ set shape "person"
          set color yellow
          set size 2
          set time-since-last-found 999
          pen-down
  ]
  reset-ticks
end

---

to go
  ask turtles [search]
  tick
end

---

to search
   ifelse time-since-last-found < 20 [
          right (random 181) - 90
   ] [
          right (random 21) - 10
   ]
   fd 1
   ifelse pcolor = red [
          set time-since-last-found 0 set pcolor blue
   ] [
          set time-since-last-found time-since-last-found + 1
   ]
end

Answer 1

It sounds like you want the turtles to stop when all the red patches have been visited, i.e., when all the red patches have been turned to blue. Adding

if count patches with [pcolor = red] <= 0 [stop]

just before tick in the go procedure should do the trick.