说明：  vscode多文件的步骤，编写多文件后，新建CMakeLists.txt，选择左边的cmake按钮，点击生成cmake并生成build文件，左边目录会看见build，cmake成功如图所示为成功
(Steps of vscode multiple files, after writing multiple files, create a new CMakeLists.txt, select the cmake button on the left, click Generate cmake and generate the build file, the left directory will see the build, cmake succeeds as shown in the figure as success)