Lua字典树：多词匹配的前缀树存储

local function scan(text)
    for _, w in ipairs(WORDS) do
        text = string.gsub(text, w, "*")   -- 80词扫80遍正文
    end
    return text
end

local ROOT = {}
for _, w in ipairs(WORDS) do
    local node = ROOT
    for i = 1, #w do
        local ch = string.sub(w, i, i)
        node[ch] = node[ch] or {}
        node = node[ch]             -- 逐字建层
    end
    node.endMark = true
end
local function scan(actor, text)
    for i = 1, #text do
        local node, j = ROOT, i
        while node[string.sub(text, j, j)] do
            node = node[string.sub(text, j, j)]
            if node.endMark then
                sendmsg(actor, 1, "命中敏感词于位置 " .. i)
            end
            j = j + 1
        end
    end
end