#include <bits/stdc++.h>
#include "boxes.h"
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define MASK(i) (1ULL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ll mask){return __builtin_ctzll(mask);}
int logOf(ll mask){return 63 - __builtin_clzll(mask);}
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b) {a = b; return true;}
return false;
}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b) {a = b; return true;}
return false;
}
template <class T>
void printArr(T& container, string separator = " ", string finish = "\n", ostream &out = cout){
for(auto item: container) out << item << separator;
out << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
const ll INF = 1e18;
ll delivery(int n, int k, int L, int p[]) {
vector<int> a;
for(int i = 0; i<n; ++i) a.push_back(p[i]);
ll ans = INF;
for(int i = 0; i<n; i += k){
int l = i, r = min(i + k - 1, n - 1);
ll cur = min({a[r] * 2, L, (L - a[l]) * 2});
ans += cur;
}
vector<int> valid;
if (n % k == 0) valid = {0, k};
else valid = {0, n % k};
for(int t: valid){
for(int l = -1; l < t; ++l)
for(int r = n; (n - r) + l + 1 <= t; --r){
ll cur = 0;
if (l >= 0) cur += a[l] * 2;
if (r < n) cur += (L - a[r]) * 2;
for(int i = l + 1; i < r; i += k){
int x = i, y = min(i + k - 1, n - 1);
cur += min({a[y] * 2, L, (L - a[x]) * 2});
}
minimize(ans, cur);
}
}
return ans;
}
// int main(void){
// ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
// return 0;
// }
