import strutils, math


proc nextString: string =
  result = ""
  while not endOfFile stdin:
    let nextChar = readChar stdin
    case nextChar
    of '\r':
      discard
    of "\n"[0], ' ':
      break
    else:
      add result, nextChar


proc nextInt: int =
  parseInt nextString()


let
  R, G, B = nextInt()
  S = [R, G, B].min

var
  L = [R, G, B].max
  M = [R, G, B].sum - S - L
  ans = 0


proc main: void =
  (ans, M, L) = (S, M - S, L - S)

  while M != 0:
    let tmp = min(M, L div 3)
    ans += tmp
    M -= tmp
    L -= tmp * 3

    if L < M:
      swap(M, L)

  ans += L div 5
  echo ans


when isMainModule:
  main()