why can't load big 3ds

i rewrite some codes to load 3ds model,
when the model at 3-4K,it run perfectly,
but it can’t load 3-4M models.why?

i check variable types,they are correct.
i haven’t find overflow either.

it is same to many example codes i have download.

The 3ds format have a limit where each object can have a maximum of 2^16 (~65535) vertices.

Sorry, but the only way is to use another format or write your own exporter.

now,after adjusting some variable type,the data imported seems correct.
the new question comes on about display format ,i’m looking for the wrong place.
thanks anyway.