how to calculate no of stereoisomers in cyclic compound

dear bhavika 
you can calculate the no of stereoisomers by the formula = 2 power n rule . 
where n is the no of chiral center. 
a couple of things to keep in mind while calculating 
1- stereoisomers are the compound with same chemical formula but diffrent spatial arrengement . 
2- and chiral centres are carbons that are bonded to 4 diffrent group . 
but in case of molecular symmetry u cannot use it . 
in case the molecule is unsyymetrical then 
total no of stereoisomers = no of optical isomers + no of meso forms . 
HOPE IT CLEARS 
REGARDS