mathe lernen mit CC

c=peripheral.wrap("top")
difficulty=20
Mode={"+","-","*","/"}
while true do
i1=math.random(1,difficulty)
i2=math.random(1,difficulty)
mode=math.random(1,4)
c.say(tostring(i1)..Mode[mode]..tostring(i2))
if mode==1 then res=i1+i2 end
if mode==2 then res=i1-i2 end
if mode==3 then res=i1*i2 end
if mode==4 then res=math.floor(i1/i2*100)/100
e,player,message = os.pullEvent("chat")
while message~=tostring(res) do
print(player..message)
e,player,message = os.pullEvent("chat")
end
c.say(player.." du hast recht!")
sleep(1)
end