L, R, C = gets.split.map(&:to_i)
memo = Hash.new(false)

ans = Float::INFINITY
cur = L

loop {
  otsuri = (C * cur) % 1000
  ans = otsuri if ans > otsuri
  break if memo[otsuri]
  memo[otsuri] = true
  cur += 1
  break if cur > R
}

puts ans