I don't usually smoke cigs, but i had one and i'm wondering how long i should wait to breastfeed? 10 pts?

i haven't smoked a cig since before i got pregnant, so it's been a long long time. i'm not planning on smoking anymore until i'm done breastfeeding, but i was wondering how long nicotine stays in your system & when it's okay for me to breastfeed again.