Auto Symbol - anyone should create a macro

if for instance i copied an element in several pages.

if i choose the command auto symbol. by selecting that element..

then it caluculates the whole document and says this element is copies across the 

whole document for 35 times. do you want all of them removed and put them as a single symbol.

if i press yes then it turns that element into symbol and whole document that element is a single symbol.

if i press no, then nothing happens, 

so please someone create a macro 

thanking you all