creating classid with -1 all .txt file

[angyee]

when I am running this script then creating classid with -1 all .txt file
in my case lut["1"] = 1
lut["2"] = 2
lut["3"] = 3
is I am doing mistake?

[LeeChungHyun]

When we use lut(Look Up Table)function, the data must be positive(0-255)
try to make the positive classid

[angyee]

When we use lut(Look Up Table)function, the data must be positive(0-255)
try to make the positive classid

how, just like lut [1] = 1
and so on