#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<vector>
#include<cmath>
#include<algorithm>
#include<map>
#include<queue>
#include<deque>
#include<iomanip>
#include<tuple>
#include<cassert>
#include<set>
#include<complex>
#include<numeric>
#include<functional>
#include<unordered_map>
#include<unordered_set>
#include<bitset>
using namespace std;
typedef long long int LL;
typedef pair<int,int> P;
typedef pair<LL,LL> LP;
const int INF=1<<30;
const LL MAX=1e9+7;

void array_show(int *array,int array_n,char middle=' '){
    for(int i=0;i<array_n;i++)printf("%d%c",array[i],(i!=array_n-1?middle:'\n'));
}
void array_show(LL *array,int array_n,char middle=' '){
    for(int i=0;i<array_n;i++)printf("%lld%c",array[i],(i!=array_n-1?middle:'\n'));
}
void array_show(vector<int> &vec_s,int vec_n=-1,char middle=' '){
    if(vec_n==-1)vec_n=vec_s.size();
    for(int i=0;i<vec_n;i++)printf("%d%c",vec_s[i],(i!=vec_n-1?middle:'\n'));
}
void array_show(vector<LL> &vec_s,int vec_n=-1,char middle=' '){
    if(vec_n==-1)vec_n=vec_s.size();
    for(int i=0;i<vec_n;i++)printf("%lld%c",vec_s[i],(i!=vec_n-1?middle:'\n'));
}

namespace sol{
    const LL N=1111;
    bitset<N> A,B;
    bitset<N*N*2> C;
    LL n,m;

    bool check(){
        LL i,j,k;
        LL a,b,c;
        LL mod=-1;
        C.reset();
        if(m<n)return A[m];
        for(i=0;i<n;i++){
            if(B[i])mod=n-i;
            C[i]=A[i];
        }
        if(mod==-1)return false;
        for(i=0;i<n;i++){
            for(j=0;j<n;j++){
                C[n+i]=C[n+i]|(C[i+j]&B[j]);
            }
        }
        vector<char> used(mod);
        for(i=n;i<N*N;i+=mod){
            for(j=0;j<mod;j++){
                if(used[j] || !C[i+j])continue;
                for(k=1;k<=n;k++){
                    if(B[n-k])C[i+j+k]=1;
                }
                used[j]=1;
            }
            for(j=0;j<mod;j++){
                C[i+mod+j]=C[i+mod+j]|C[i+j];
            }
        }
        if(m<N*N)return C[m];
        LL pos=m-(m-i)/mod*mod;
        return C[pos];
    }

    void solve(){
        LL i,j,k;
        LL a,b,c;
        cin>>n>>m;
        vector<LL> v1,va,vb;
        for(i=0;i<n;i++){
            cin>>a;
            va.push_back(a);
            v1.push_back(a);
        }
        for(i=0;i<n;i++){
            cin>>a;
            vb.push_back(a);
            v1.push_back(a);
        }
        sort(v1.begin(),v1.end());
        LL z[3]={-1,v1.size()};
        while(z[1]-z[0]>1){
            z[2]=(z[0]+z[1])/2;
            a=v1[z[2]];
            A.reset(),B.reset();
            for(i=0;i<n;i++){
                if(va[i]>=a)A.set(i,1);
                if(vb[i]>=a)B.set(i,1);
            }
            if(check())z[0]=z[2];
            else z[1]=z[2];
        }
        cout<<v1[z[0]]<<endl;
    }
}

int main(){
    sol::solve();
}