Scoreboard

function exchange(list,y,page)
    w,h = term.getSize()
    y=y+(h-1)*(page-1)
    local l = list[y]
    if y<=#list then
        invcheck = "execute unless entity @p[nbt={Inventory:[{id:\""..l[3].."\",Count:"..l[4].."b}]}] run "
        checkstr = "execute if entity @p[nbt={Inventory:[{id:\""..l[3].."\",Count:"..l[4].."b}]}] run "
        checkmoney = "execute if entity @p[scores={money="..l[2].."..}] run "
        invcheckmoney = "execute unless entity @p[scores={money="..l[2].."..}] run "
        if l[1] == "buy" then
            exec(checkmoney.."give @p "..l[3].." "..l[4])
            exec(checkmoney.."tellraw @p [{\"text\":\"Success! (You had \",\"color\":\"green\"},{\"score\":{\"name\":\"*\",\"objective\":\"money\"},\"color\":\"green\"},{\"text\":\"$)\",\"color\":\"green\"}]")
            exec(invcheckmoney.."tellraw @p [{\"text\":\"Not enough money! (You have \",\"color\":\"red\"},{\"score\":{\"name\":\"*\",\"objective\":\"money\"},\"color\":\"red\"},{\"text\":\"$)\",\"color\":\"red\"}]")
            exec(checkmoney.."scoreboard players remove @p money "..l[2])
        else
            exec(checkstr.."scoreboard players add @p money "..l[2])
            exec(checkstr.."tellraw @p [{\"text\":\"Success! (You have \",\"color\":\"green\"},{\"score\":{\"name\":\"*\",\"objective\":\"money\"},\"color\":\"green\"},{\"text\":\"$)\",\"color\":\"green\"}]")
            exec(invcheck.."tellraw @p [{\"text\":\"Not enough items!\",\"color\":\"red\"}]")
            exec(checkstr.."clear @p "..l[3].." "..l[4])
        end
        exec(checkstr.."clear @p "..l[1].." "..l[2])
    end
end
function draw(list,page)
    term.redirect(peripheral.wrap("top"))
    peripheral.wrap("top").setTextScale(0.5)
    term.clear()
    term.setCursorPos(1,1)
    w,h = term.getSize()
    pages = 1
    if h>#list then
        pages = math.floor(#list/(h-1))
    end
    for i=1+(h-1)*(page-1),(h-1)*page do
        if i>#list then break end
        if list[i][1] == "sell" then
            print(list[i][4].." "..list[i][3].." -> "..list[i][2].."$")
        else
            print(list[i][2].."$ -> "..list[i][4].." "..list[i][3])
        end
    end
    term.setCursorPos(1,h)
    write("<<<")
    term.setCursorPos(math.floor(w/2),h)
    write(page)
    term.setCursorPos(w-2,h)
    write(">>>")
end
--------------+
page = 1   --+#
table = {} --+#
--------------+
table[1] = {"sell",42,"minecraft:dirt",1}
table[2] = {"buy",69,"minecraft:amethyst_shard",1}
---------------
draw(table,page)
while true do
    name,side,x,y = os.pullEvent("monitor_touch")
    w,h = term.getSize()
    if y<h then
        exchange(table,y,page)
    else
        if x<w/2 then
            page=page-1
            if page<1 then
                page = math.ceil(#table/(h-1))
            end
        else
            page=page+1
            if page>math.ceil(#table/(h-1)) then
                page = 1
            end
        end
    end
    draw(table,page)
end