function getKeywords(text)
    if not text then return {} end
    local s = tostring(text):lower()
    
    local keywords = {}
    
    for code in s:gmatch("[%a%d]+%-[%a%d]+") do
        keywords[code] = true
    end
    for code in s:gmatch("%a+%d+") do
        keywords[code] = true
    end
    
    for zh in s:gmatch("[\128-\255]+") do
        local cleanZh = zh:gsub("站台", ""):gsub("轨道", ""):gsub("号", ""):gsub("线", "")
        if cleanZh and cleanZh ~= "" then
            keywords[cleanZh] = true
        end
    end
    
    local list = {}
    for k, _ in pairs(keywords) do
        table.insert(list, k)
    end
    return list
end

local function test(a, b)
    local k1 = getKeywords(a)
    local k2 = getKeywords(b)
    local match = false
    for _, w1 in ipairs(k1) do
        for _, w2 in ipairs(k2) do
            if w1 == w2 or w1:find(w2, 1, true) or w2:find(w1, 1, true) then
                match = true
                break
            end
        end
    end
    print(a .. " vs " .. b .. " -> " .. tostring(match))
    print("  K1: " .. table.concat(k1, ", "))
    print("  K2: " .. table.concat(k2, ", "))
end

test("CE-03 (桃园)", "桃园")
test("CE-04", "CE-04 [西门]")
test("CRH-01", "CRH-01 南山线")
test("南山线", "南山")
test("???", "Unknown")