import scala.annotation.tailrec
import scala.io.StdIn.*
import scala.math.min
def calcFactorInFactorial(n: Long, m: Long): Long =
  n match
    case 0L => 0
    case _ => n / m + calcFactorInFactorial(n / m, m)

def calcPrimeFactor(value: Long): List[(Long, Int)] =
  @tailrec def inner(v: Long, p: Long, result: List[(Long, Int)]): List[(Long, Int)] =
    if p * p > v then
      if v > 1 then (v, 1)::result else result
    else if v % p == 0 then
      var e = 0
      var r = v
      while r % p == 0 do
        e += 1
        r /= p
      inner(r, p + 1, (p, e)::result)
    else
      inner(v, p + 1, result)
  inner(value, 2, Nil)

@main def main =
  val Array(n, k, m) = readLine().split(' ').map(_.toLong)
  var result = Long.MaxValue
  for (p, e) <- calcPrimeFactor(m) do
    val cFactor = calcFactorInFactorial(n, p) - calcFactorInFactorial(k, p) - calcFactorInFactorial(n - k, p)
    result = min(result, cFactor / e)
  println(result)