R語言中安裝 maptools 包

001、R語言中安裝maptools出現如下問題：

> install.packages("maptools")
將程式包安裝入‘C:/Users/liujiaxin/AppData/Local/R/win-library/4.3’
(因為‘lib’沒有被指定)
Warning in install.packages :
  package ‘maptools’ is not available for this version of R

A version of this package for your version of R might be available elsewhere,
see the ideas at
https://cran.r-project.org/doc/manuals/r-patched/R-admin.html#Installing-packages

002、