local mma = math.max
local n = io.read("*n")
local t = {}
for i = 1, n do
  local x, y, z = io.read("*n", "*n", "*n")
  if y < x then x, y = y, x end
  if z < x then x, z = z, x end
  if z < y then y, z = z, y end
  t[i] = {x, y, z}
end
local function sortfunc(a, b)
  if a[1] ~= b[1] then
    return a[1] < b[1]
  elseif a[2] ~= b[2] then
    return a[2] < b[2]
  else
    return a[3] < b[3]
  end
end
table.sort(t, sortfunc)
local v = {}
v[1] = 1
for i = 2, n do
  local cand = 1
  for j = 1, i - 1 do
    if t[j][1] < t[i][1] and t[j][2] < t[i][2] and t[j][3] < t[i][3] then
      cand = mma(cand, v[j] + 1)
    end
  end
  v[i] = cand
end
local ret = 1
for i = 1, n do ret = mma(ret, v[i]) end
print(ret)