import sequtils,math
proc getchar_unlocked():char {. importc:"getchar_unlocked",header: "<stdio.h>" .}
proc scan(): int =
  while true:
    let k = getchar_unlocked()
    if k < '0': break
    result = 10 * result + k.ord - '0'.ord

let n = scan()
const INF = 1000_0010
const C = (proc():seq[int] =
  result = @[]
  for i in 1..INF:
    let c = i * (i + 1) div 2
    if c > INF : break
    result &= c
)()
block:
  let nsq = (n*2).float.sqrt.int
  if nsq * (nsq + 1) div 2 == n: quit "1", 0
for i in 0..<C.len:
  for j in i..<C.len:
    let c = C[i] + C[j]
    if n == c: quit "2",0
    if c > n : break
echo 3