import copy
j=0
n,hp=map(int,input().split(" "))
la=[0 for i in range(n)]
lb=[0 for i in range(n)]
for i in range(n):
    la[i],lb[i]=map(int,input().split(" "))
cnt=0
ma=max(la)
lma=[i for i ,x in enumerate(la)  if x==ma]
mib=10**9
for i in lma:
    if lb[i]<mib:
        mib=lb[i]
        k=i
tmp=copy.deepcopy(lb)
while max(tmp)>ma:
    hp-=max(tmp)
    tmp.remove(max(tmp))
    cnt+=1
    if hp<0:
        print(cnt)
        j=1
if hp%ma==0 and j==0:
    print(cnt+int(hp/ma))
elif j==0:
    print(cnt+int(hp/ma)+1)