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rednet.open("top")
 
local file = fs.open("disk/items.txt","r")
CurrItems = textutils.unserialise(file.readAll())
file.close()
 
local map = {
    [1] = false, [2] = false,  [3] = false,
    [5] = false, [6] = false,  [7] = false,
    [9] = false, [10] = false, [11] = false
}
 
while true do
    id, msg = rednet.receive()
    item = string.sub(msg,string.find(msg,":")+1)
    if (CurrItems[item] ~= nil) then
        rednet.send(id,CurrItems[item].location)
    else
        currBestX = 0
        currBestY = 0
        for k,v in pairs(CurrItems) do
            if (CurrItems[k].location[1] > currBestX) then
                currBestX = CurrItems[k].location[1]
            end
            if (CurrItems[k].location[2] > currBestY) then
                currBestY = CurrItems[k].location[2]
            end
        end
        if (currBestX + 1 > 4) then
            y = currBestY + 1
            x = 0
        else
            x = currBestX + 1
        end
 
        CurrItems[item] = {
            count = 1,
            location = {tonumber(x),tonumber(y)},
            map = map
        }
 
        File = fs.open("disk/items.txt", "r")
        FileData = textutils.unserialise(File.readAll())
        table.insert(FileData[item], CurrItems[item])
        File.close()
        File = fs.open("disk/items.txt", "w")
        File.write(textutils.serialise(FileData))
        File.close()