#include<bits/stdc++.h>
using namespace std;
using i64=long long;
constexpr int B=200;
int n,K,a[50010],b[50010],c[50010];
namespace pre{
vector<int>val;
priority_queue<pair<int,int>>q;
int cur[50010];
inline void ins(int i){
   if(cur[i]>=n)return;
   cur[i]++;
   q.emplace(-(b[i]+c[cur[i]]),i);
}
void work(){
   for(int i=1;i<=n;i++)ins(i);
   for(;!q.empty()&&val.size()<5000000;){
      auto X=q.top();q.pop();
      val.push_back(-X.first),ins(X.second);
   }
}
}
int calc(i64 v){
   int res=0;
   for(int i=1,j=n;i<=n;i++){
      for(;j>=1&&b[i]+c[j]>v;j--);
      res=min(res+j,K);
   }return res;
}
bool check(i64 M){
   if(n<=B){
      int s=0;
      for(int i=1;i<=n;i++){
         s+=calc(M-a[i]);
         if(s>=K)return true;
      }return false;
   }
   int f0=calc(M-a[B]);
   if(f0>=(K-1)/B+1)return true;
   int s=f0;
   for(int i=1;i<B;i++){
      s+=calc(M-a[i]);
      if(s>=K)return true;
   }
   for(int i=B+1;i<=n;i++){
      s+=upper_bound(begin(pre::val),end(pre::val),M-a[i])-begin(pre::val);
      if(s>=K)return true;
   }
   return false;
}
int main(){
   scanf("%d%d",&n,&K);
   for(int i=1;i<=n;i++)scanf("%d",&a[i]);
   for(int i=1;i<=n;i++)scanf("%d",&b[i]);
   for(int i=1;i<=n;i++)scanf("%d",&c[i]);
   sort(a+1,a+n+1),sort(b+1,b+n+1),sort(c+1,c+n+1);
   i64 l=0,r=3000000000;
   while(l<r){
      i64 mid=l+r>>1;
      if(check(mid))r=mid;
      else l=mid+1;
   }
   printf("%lld",l);
   return 0;
}