n,k=map(int,input().split())
a=list(map(int,input().split()))
b=list(map(int,input().split()))
c=list(map(int,input().split()))
g=sum(a[i]+c[i] for i in range(n))
print(g+sum(sorted([b[i]-c[i] for i in range(n)])[n-k:]))