Timer 时间到了，在继续之前先让它工作起来。 globals [ count-tick ] turtles-own [ speed flag-A ] to setup clear-all resize-world 0 50 min-pycor max-p

时间到了，在继续之前先让它工作起来。

globals [ count-tick ]
turtles-own [ speed flag-A ]

to setup
  clear-all
  resize-world 0 50 min-pycor max-pycor
  ask patches [ setup-road ]
  reset-ticks
end

to setup-road
  if ( pycor < 1 ) and ( pycor > -1 ) [ set pcolor white ]
end

to create-car
  crt 1 [
    set color blue
    setxy min-pxcor 0
    set heading 90
    set speed 1
  ]
end

to go

  if (count turtles-on patch 0 0 = 0) [
    create-car
    ask (turtles-on patch 0 0) [
      set flag-A FALSE
    ]
  ]

  ask (turtles-on patch 10 0) [
    set flag-A TRUE
    set count-tick 10
  ]

  if count-tick > 0 [
    set count-tick count-tick - 1
    ask (turtles-on patch 10 0) with [flag-A = TRUE]
    [
      set color red
      set speed 0
    ]
  ]

  if count-tick = 0 [
    ask (turtles-on patch 10 0) with [flag-A = TRUE]
      [
        set speed 1
        set flag-A FALSE
    ]
  ]

  if (count turtles-on patch max-pxcor 0 > 0) [
    ask min-one-of turtles [who][
      die
    ]
  ]

  set-speed
  tick
end

to set-speed
  ask turtles with [ xcor < 10 ] [
    let turtle-ahead one-of turtles-on patch-ahead 1
    ifelse turtle-ahead = nobody
      [ set speed 1
        fd speed
    ]
    [ set speed 0
    ]
  ]
    ask turtles with [ 10 < max-pxcor ] [
    let turtle-ahead one-of turtles-on patch-ahead 1
    ifelse turtle-ahead = nobody
      [ set speed 1
        fd speed
    ]
    [ set speed 0
    ]
  ]
end

globals [ count-tick ]
turtles-own [ speed flag-A ]

to setup
  clear-all
  resize-world 0 50 min-pycor max-pycor
  ask patches [ setup-road ]
  reset-ticks
end

to setup-road
  if ( pycor < 1 ) and ( pycor > -1 ) [ set pcolor white ]
end

to create-car
  crt 1 [
    set color blue
    setxy min-pxcor 0
    set heading 90
    set speed 1
    set flag-A FALSE
  ]
end

to go

  if (count turtles-on patch 0 0 = 0) [
    create-car
  ]

  ask (turtles-on patch 10 0) [
    set flag-A TRUE
    set count-tick 10
  ]

  ask (turtles-on patch 10 0) with [flag-A = TRUE] [
    set color red
    set speed 0
    set count-tick count-tick - 1

    if count-tick = 0 [
      set speed 1
      set flag-A FALSE
    ]
  ]

  if (count turtles-on patch max-pxcor 0 > 0) [
    ask min-one-of turtles-on patch max-pxcor 0 [who][
      die
    ]
  ]

  ask turtles [ forward speed ]

  tick
end