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import Std

def Main : IO Unit := do
  let A := Array.replicate 10 0 |>.append (Array.replicate 8 1) |>.append (Array.replicate 6 2)
  let N := A.size
  let mut cnt := 0
  for ha : a in 0...N do
    for hb : b in (a + 1)...N do
      for hc : c in (b + 1)...N do
        for hd : d in (c + 1)...N do
          for he : e in (d + 1)...N do
            if ({ A[a], A[b], A[c], A[d], A[e] } : Std.HashSet Nat).size = 3 then
              cnt := cnt + 1
  IO.println cnt

#eval Main