An example of using dict_tree to set tag for each records in data set
go get -u github.com/brg-liuwei/dict_tree
go get -u github.com/brg-liuwei/dict_tree_main
export $PATH=$PATH:$GOPATH/bin
dict_tree_main <tags_file> <records_file>
data/cities: tags file, the format is which city names on the 1st column and tag on the 2nd column
data/records: records file, each line of this file is a record waiting for processing