"it good that smoking is ban inside the malls .. but you get one huge dose while entering or leaving mall .. what about that ?"

I'm not a smoker anymore, but people like you really piss me off. It's a tiny bit of smoke when you enter a mall, tiny compared to the amount of CO and other nasties produced by traffic.
You're one of those that does that annoying false cough when you walk by a smoker I presume? and yet will sit outside and enjoy a BBQ on a lovely spring day? *hint* BBQ'd food contains carcinogens.
If it bothers you so much then hold your breath when you enter or leave a mall.

Now smoking laws inside the malls just need to be banned, or so as they have in the costa by megamart, have a smoking section in cafe's with extractors.