Population vs Trash

globals [ max-trash max-population all-shapes ]
breed [person people]
breed [trash trashes]

to setup
  clear-all
  set max-trash 10000
  reset-ticks
end 

to move
  rt random 50
  lt random 50
  fd 1
end 

to go
  add
  if not any? turtles [ stop ]
  ;;if not any? population and (electronics-life + clothes-life + food-life) > max-population [ user-message "The trash have inherited the earth" stop ]
  ask turtles with [ shape = "food" ] [ setxy random 40 random 40 ]
  ask turtles with [ shape = "person graduate" ] [ setxy random 40 random 40 ]
  ask turtles with [ shape = "computer workstation" ] [ setxy random 40 random 40 ]

  ask turtles with [ shape = "food" ] [
    if ticks > food-life [ die ]
  ]
  ask turtles with [ shape = "person graduate"] [
    if ticks > clothes-life [ die ]
  ]
  tick
end 

to add
  create-turtles 5 [setxy random electronics-life random electronics-usage-length
    set shape "computer workstation"
  ]
  create-turtles 3 [setxy random clothes-life random clothes-usage-length
    set shape "person graduate"
  ]
  create-turtles 6 [setxy random food-life random food-usage-length
    set shape "food"
  ]
end