local t = io.read("*n")

local function dotask()
  local n = io.read("*n")
  local l = {}
  for i = 1, n do
    local tmp = io.read("*n")
    if(l[tmp] == nil) then l[tmp] = 1 else l[tmp] = l[tmp] + 1 end
  end
  local mcnt = 0
  for k, v in pairs(l) do
    mcnt = math.max(mcnt, v)
  end
  local c = {}
  for i = 1, mcnt do c[i] = 0 end
  local remall = 0
  for k, v in pairs(l) do
    c[v] = c[v] + 1
    remall = remall + 1
  end
  local ret = 0
  while(3 <= remall) do
    ret = ret + 1
    for i = 1, 3 do
      c[mcnt] = c[mcnt] - 1
      if(c[mcnt] == 0) then mcnt = mcnt - 1 end
      if(1 < mcnt) then
        c[mcnt - 1] = c[mcnt - 1] + 1
      else
        remall = remall - 1
      end
    end
  end
  return ret
end

for i = 1, t do
  print(dotask())
end