does not compute (30/35)?!?!?!?!?!!!?!?!?!

i found somthing very odd dand disturbing my compiler will no compute the number 30/35 or other fractions of the same value .
it will not cout it or output it by any other means, including stoping the program with the debugging tool and observing the program directly
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!
wtf!!!

Does it work with 30.0/35.0 ?

some how yes

That's because 30 and 35 are integers and if you divide integers you won't get any remainder so 30/35=0.