import sequtils,strutils,algorithm,math,future,macros
template get*():string = stdin.readLine().strip()
template `min=`*(x,y:typed):void = x = min(x,y)

let V = get().split().map(parseInt).sorted(cmp) # 4 * [1,30]
const INF = 1e6.int
var ans = INF
# 30 * 30 * 30
proc getABCCost() : array[31,array[31,array[31,array[31,int]]]] =
  for a in 0..30:
    for b in 0..30:
      for c in 0..30:
        for d in 0..30:
          result[a][b][c][d] = INF
  for A in 1..30:
    for B in 1..A:
      for C in 1..B:
        var dp = newSeqWith(30+1,INF) # v を ABC で 作るのに掛かるコストの最小値
        dp[0] = 0
        for v in 0..30-A:
          if dp[v] != INF: dp[v + A] .min= dp[v] + 1
        for v in 0..30-B:
          if dp[v] != INF: dp[v + B] .min= dp[v] + 1
        for v in 0..30-C:
          if dp[v] != INF: dp[v + C] .min= dp[v] + 1
        for v in 0..30: result[A][B][C][v] = dp[v]
const ABC = getABCCost()
for A in 1..V.max():
  for B in 1..A:
    for C in 1..B:
      ans .min= V.mapIt(ABC[A][B][C][it]).sum()
echo ans