tree.o tree.d : tree.cc /usr/class/cs143/cool/include/PA3/copyright.h \
 /usr/class/cs143/cool/include/PA3/tree.h \
 /usr/class/cs143/cool/include/PA3/copyright.h \
 /usr/class/cs143/cool/include/PA3/stringtab.h \
 /usr/class/cs143/cool/include/PA3/list.h \
 /usr/class/cs143/cool/include/PA3/cool-io.h