const Main = (input) => {
  const tmp = input.split(' ')
  const takahashi = { hp: tmp[0], atk: tmp[1] }
  const aoki = { hp: tmp[2], atk: tmp[3] }

  let i = 0
  let result = ''
  let winner = ''

  const player = { takahashi: takahashi, aoki: aoki }
  const players = ['takahashi', 'aoki']
  while (true) {
    const attacker = players[i % 2]
    const defender = players[(i + 1) % 2]
    player[defender].hp = player[defender].hp - player[attacker].atk
    if (player[defender].hp <= 0) {
      winner = attacker
      break
    }
    i += 1
  }

  if (winner === 'takahashi') {
    result = 'yes'
  } else {
    result = 'no'
  }

  console.log(result)
  return result
}

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