num = map(int, raw_input())
keiken = list(map(int, raw_input().split()))
ma = 0
ins = 0
alls = 0
for i in range(num):
	alls += keiken[i]/2

	if ma < keiken[i]/2:
		ma = keiken[i]/2
		ins = i
alls = alls - keiken[ins]/2 + keiken[ins]
print alls