n,p1,p2=map(int,input().split())
c=[tuple(map(int,input().split())) for i in range(n)]
q=[0]*(1<<n)
for i in range(1<<n):
  a=0
  b=0
  for j in range(n):
    if (i>>j)&1:
      a+=c[j][0]
      b+=c[j][1]
  if a<=p1:
    q[i]=b
for j in range(n):
  for i in range(1<<n):
    if (i>>j)&1:
      q[i]=max(q[i],q[i^(1<<j)])
g=0
for i in range(1<<n):
  a=0
  b=0
  for j in range(n):
    if (i>>j)&1:
      a+=c[j][0]
      b+=c[j][1]
  if a<=p2:
    g=max(g,b+q[((1<<n)-1)^i])
print(g)