Lua程序设计第4版第11章课后练习答案

11.1
修改模式匹配中的%w+为%w%w%w%w+

    for line in io.lines() do
        for word in string.gmatch(line,"%w%w%w%w+") do
            counter[word] = (counter[word] or 0)+1
        end
    end

11.2

从文本文件中读取到ingorewords单词，在循环中逐个判断

---
--- Generated by EmmyLua(https://github.com/EmmyLua)
--- Created by 15240.
--- DateTime: 2019/12/8 12:07
---

function f()
    local ingorewords= {}
    io.input("ingoreWords")
    for line in io.lines() do
        for word in string.gmatch(line,"%w+") do
            ingorewords[word] = word
        end
    end
    flag = true
    io.input("10.lua")
    local counter = {}
    for line in io.lines() do
        for word in string.gmatch(line,"%w%w%w%w+") do
            for k,v in pairs(ingorewords) do
                if v==word then
                    flag = false
                end
            end
            if flag then
                counter[word] = (counter[word] or 0)+1
            end
            flag = true
        end
    end

    local words = {}
    for w in pairs(counter) do
        words[#words+1] = w
    end

    table.sort(words,function(w1,w2)
        return counter[w1]>counter[w2] or counter[w1]==counter[w2] and w1<w2
    end)

    local n = math.min(tonumber(arg[1] or math.huge),# words)
    for i = 1, n do
        io.write(words[i],"\t",counter[words[i]],"\n")
    end
end

f()