#include "boxes.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pi;
typedef vector<pi> pii;
typedef tuple<int,int,int> ti;
typedef vector<ll> li;
typedef vector<li> lii;
#define REP(i,a,b) for(int i=a;i<b;i++)
#define F first
#define S second
#define PB push_back
#define LSOne(s) ((s)&(-s))
ll INF=1000000000000000010;
int inf=1e9+10;
ll M=1e9+7;
long long delivery(int n, int m, int L, int p[]) {
vi a;
ll c=0;
int pos=0;
while(pos<=n){
int x=p[pos];
a.PB(x);
if(pos-m>=0&&p[pos]>L/2&&p[pos-m]<L/2){
c+=L;
pos+=m;
continue;
}
x=min(x,L-x+m-1);
c+=x*2LL;
if(pos==n)break;
pos+=m;
if(pos>n)pos=n;
}
ll ans=c;
int sz=a.size();
REP(j,2,m+1){
c=0;
REP(i,0,sz){
a[i]++;
if(a[i]>n)a[i]=n;
int x=a[i];
if(i>0&&a[i]>L/2&&a[i-1]<L/2){
c+=L;
continue;
}
x=min(x,L-x+m-1);
c+=x*2LL;
}
ans=min(ans,c);
}
return ans;
}
