local ior = io.input()
local n = ior:read("*n")
local t = {}
for i = 1, n do
  t[i] = ior:read("*n")
end
table.sort(t)
local sum = 0
for i = 1, n - 1 do
  sum = sum + math.floor(t[i] / 2)
end
sum = sum + t[n]
print(sum)