Is it safe to spend the night at the airport?

It must be safe, the airport is 24 hours! I slept at the Singapore airport for one night. Transit hotels in Singapore have no internet. Just one bed, expensive! Anyway, I found a place with lounge chairs at the Singapore airport, and there were many foreigners sleeping! Just find a few people lying down and take a backpack as a pillow. Nobody cares about you. It's very common at the airport! But certainly not as comfortable as a bed!