Removing objects in an NSArray one by one

[j10j]

My NSArray has 10 entries,
and for an exercise I am told to remove the entries one by one, what is the fastest method?

for (i=9; i < 0 & i< 10; i--) {[array removeObjectAtIndex:i];}

OR


while ([array count]>0){
[array removeLastObject];
}

PS: I am aware of removeAllObjects

[Nat!]

The first piece of code is much much faster than the second one.