使用CMD时，set classpath与javac -cp与java -cp有什么区别吗？如果使用set classpath，需要把jdk的class文件目录也加上吗？
-cp
-classpath
A : separated list of directories, JAR archives,
and ZIP archives to search for class files.
-cp class search path of directories and zip/jar files
-classpath class search path of directories and zip/jar files
A : separated list of directories, JAR archives,
and ZIP archives to search for class files