#include "boxes.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
#define X first
#define Y second
const ll MAXN = 2e7 + 10;
ll ps[MAXN], ss[MAXN];
long long delivery(int N, int K, int L, int p[]) {
sort(p, p + N);
priority_queue<pll, vector<pll>, greater<pll>> pq;
pq.push({0, -1});
for (int i = 0; i < N; i++) {
while (pq.top().Y < i - K) pq.pop();
ps[i] = numeric_limits<ll>::max();
ps[i] = min(ps[i], pq.top().X + p[i] + min(L - p[i], p[i]));
pq.push({ps[i], i});
}
while (!pq.empty()) pq.pop();
ss[N] = 0;
pq.push({0, N});
for (int i = N - 1; i >= 0; i--) {
while (pq.top().Y > i + K) pq.pop();
ss[i] = numeric_limits<ll>::max();
ss[i] = min(ss[i], pq.top().X + (L - p[i]) + min(L - p[i], p[i]));
pq.push({ss[i], i});
}
ll ans = min(ps[N - 1], ss[0]);
for (int i = 0; i < N; i++)
ans = min(ans, ps[i] + ss[i + 1]);
return ans;
}
