#include "boxes.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
const ll LOG = 31;
const ll MOD = 1000000007;
const ll inf = 1e17;
const ll B = 2305843009213693951;
#define db(x) cerr << #x << " = " << x << " | "
#define dbg(x) cerr << #x << " = " << x << "\n"
#define Algerian ios::sync_with_stdio(0);
#define OI cin.tie(NULL);
ll delivery(int n, int k, int l, int p[]) {
// unordered_map<ll, ll> mp;
// for (ll i = 0; i < n; i++) mp[p[i]]++;
// // vector<pll> dq;
// vector<ll> d = {0}, w = {0}, pos = {0};
// for (auto& [u, v] : mp) pos.push_back(u);
// sort(pos.begin(), pos.end());
// ll t = pos.size();
// for (ll i = 1; i < t; i++) {
// d.push_back(pos[i] - pos[i - 1]);
// w.push_back(mp[pos[i]]);
// }
// pos.push_back(n);
// d.push_back(n - pos.back());
// w.push_back(0);
// t++;
ll res = 0;
for (ll i = 0; i < n; i++) {
res += min(p[i], l - p[i]);
}
return 2 * res;
// vector<ll> pref(t + 1), suf(t + 1), a(t + 1), b(t + 1);
// for (ll i = 1; i < t; i++) {
// a[i] = (a[i - 1] + w[i]) % k;
// ll lft = k - a[i];
// pref[i] = pref[i - 1] + 2 * d[i];
// ll now = w[i] - lft;
// pref[i] += pos[i] * w[i];
// }
// for (ll i = t - 1; i >= 0; i--) {
// }
}
