此代码包含道路设置和乌龟创建过程，之后，使乌龟走上粉红色路径的过程，并试图使乌龟变色，使其变成红色斑点，但由于未知原因，此代码不工作，汽车永远不会改变颜色并保持蓝色，因为那里有创造色 我希望我能得到一些帮助
turtles-own [
speed
s?
]
to setup-road
clear-all
ask patches [
ifelse pycor < -8 and pycor > -17 [set pcolor black ]
[set pcolor gray - 3 ]
if pycor < -9 and pycor > -15 [ set pcolor gray ]
if pycor > -10 and pycor < -8 and pxcor > 20 and pxcor < 27
[set pcolor white ]
if pycor < -2 and pycor > -4 and pxcor < 20 and pxcor > -24
[set pcolor pink ]
if pycor < -3 and pycor > -10 and pxcor < -22 and pxcor > -24
[set pcolor green ]
if pxcor = 20 and pycor = -3
[set pcolor red
]
]
set-default-shape turtles "car"
create-turtles 2 [
set color blue
set size 2
set xcor random-xcor
set ycor -12
set heading 90
set speed 0.1 + random-float 0.9
set s? true
]
reset-ticks
end
to go
ask turtles [
let car-ahead one-of turtles-on patch-ahead 2
if car-ahead != nobody
[ fd speed]
let gate one-of patches in-radius 5 with [pcolor = green ]
let path one-of patches in-radius 5 with [pcolor = pink ]
if s?
[ ifelse gate != nobody
[ move-to gate
fd speed
ifelse path != nobody
[
move-to path
fd speed
if patch-ahead 1 != nobody and pcolor != pink
[set color green ]
]
[fd speed]]
[fd speed]
]
]
tick
end