#include<bits/stdc++.h>
using namespace std;
using ll = long long int;
using ld = long double;
const ll MAX = 5000000000000000000;
const ld PI = 3.14159265358979;
const ll MOD = 1000000007;//2024948111;
random_device rd;
mt19937 mt(rd());
ld dotorad(ld K){return PI * K / 180.0;}
ld radtodo(ld K){return K * 180.0 / PI;}
int main(){
    ll N,K,P;
    cin >> N >> K >> P;
    vector<ll> A(N),B(N);
    for(ll i = 0;i < N;i++) cin >> A[i];
    for(ll i = 0;i < N;i++) cin >> B[i];
    sort(A.begin(),A.end());
    B.emplace_back(-MAX);
    B.emplace_back(MAX);
    sort(B.begin(),B.end());
    ll l = P,r = -1;
    while(l - r > 1){
        ll m = (l + r) / 2,c = 0;
        for(ll i = 0;i < N;i++){
            ll a,b;
            a = (P - 1) - A[i];
            b = m - A[i];
            ll p = N - (upper_bound(B.begin(),B.end(),a) - B.begin());
            ll q = N - (lower_bound(B.begin(),B.end(),b) - B.begin());
            a = 2 * P - 1 - A[i];
            b = P + m - A[i];
            p += N - (upper_bound(B.begin(),B.end(),a) - B.begin());
            q += N - (lower_bound(B.begin(),B.end(),b) - B.begin());
            c += q - p;
        }
        //cout << m << "/" << c << endl;
        if(c < N * N - K + 1) l = m;
        else r = m;
    }
    cout << r << endl;
}