#include <bits/stdc++.h>
#include <iostream>
#include "boxes.h"
using namespace std;
#define rep(i,a,b) for(int i = a; i < b; i++)
#define pb push_back
#define lso(x) x&(-x)
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
int n, k, l;
vi p;
vi pos;
ll min(ll a, int b) {return min(a, (ll)b);}
ll kone() {
ll ans = 0;
rep(i,0,n) {
ans += 2*min(pos[i], l - pos[i]);
}
return ans;
}
ll kn() {
ll ans = l;
rep(i,0,n - 1) {
ans = min(ans, 2*pos[i] + 2*(l - pos[i + 1]));
}
return ans;
}
ll n10() {
return 0;
}
ll delivery(int N, int K, int L, int positions[]) {
n = N; k = K; l = L;
pos.resize(n); rep(i,0,n) pos[i] = positions[i];
if (k == 1) return kone();
else if (k == n) return kn();
else if (n <= 10) return n10();
return 0;
}
