object Main extends App {
	val nh = scala.io.StdIn.readLine.split(" ").map(_.toLong)
	var a = new Array[Long](nh(0).toInt)
	var b = new Array[Long](nh(0).toInt)

	for(i<-0 until nh(0).toInt){
		val temp = scala.io.StdIn.readLine.split(" ").map(_.toLong)
		a(i) = temp(0)
		b(i) = temp(1)
	}

	b = b.sorted.reverse

	val max = a.max
	var ans = 0
	var temp = nh(1)

	for(i<-0 until nh(0).toInt){
		if(temp <=0){

		}else if(b(i) >= max){
			temp -= b(i)
			ans += 1
		}
	}

	if(temp <=0) println(ans)
	else println(ans + (temp + max - 1)/max)


}