#yuki949

n=int(raw_input())
a=map(int,raw_input().split())
b=map(int,raw_input().split())
d=map(int,raw_input().split())
a.reverse()
b.reverse()
d.sort()
dp=[[0 for i in range(3003)] for j in range(3003)]
for i in range(n+1):
 for j in range(n+1):
  if i>0:
   dp[i][j]=max(dp[i][j],dp[i-1][j])
  if j>0:
   dp[i][j]=max(dp[i][j],dp[i][j-1])
  if dp[i][j]==n:
   continue
  if i==n and j==n:
   continue
  if a[i]+b[j]>=d[dp[i][j]]:
   dp[i][j]+=1
print dp[n][n]