const Main = (input) => {
  const X = BigInt(input.trim())
  let deposit = 100

  let result = 0

  while (deposit < X) {
    deposit = Math.floor(deposit * 1.01)
    result += 1
  }

  console.log(result)
  return result
}

Main(require('fs').readFileSync('/dev/stdin', 'utf8'))