n,h = map(int,input().split())
x = []
for i in range(n):
	x.append(list(map(int,input().split())))
a = []
for i in range(n):
	a.append(x[i][0])
b = []
for i in range(n):
	b.append(x[i][1])
x.sort(key = lambda x:x[1])

t = 0
c = []
if sum(b)>h-1:
	for i in range(n):
		t += 1
		h -= x[i+1][1]
		if h<1:
			print(t)
			break
else:
	for i in range(n):
		if b[i]>max(a)-1:
			c.append(b[i])
	h -=sum(c)
	q = h//max(a)
	print(q+len(c))
