ruby字符串连接

malls = Mall.all
count = 0
malls.each do |mall|
    count += 1
    if mall.parent_ids[0]
        province = Province.find(mall.parent_ids[0])
        if !mall.address.include?(province.name)
           mall.address = province.name + mall.address
           mall.save
           p mall.address
           p count
        end
    end
end