#include "boxes.h"
#include <stdio.h>
#include <iostream>
#include <string>
#include <set>
#include <map>
#include <cstring>
#include <unordered_map>
#include <vector>
#include <fstream>
#include <bitset>
#include <tuple>
#include <cmath>
#include <cstdint>
#include <stack>
#include <cassert>
#include <cstdio>
#include <queue>
#include <iterator>
#include <iomanip>
#include <algorithm>
#include <sstream>
using namespace std;
int L;
int leftDist(int s, int t) { return t-s; }
int rightDist(int s, int t) { return s+(L - t); }
int dist(int s, int t) { return min(leftDist(s,t), rightDist(s, t)); }
long long delivery(int N, int K, int l, int p[]) {
L = l;
long long sum = 0;
if (K == N) {
int c = 0;
int lastdist = 0;
bool ldir=true;
while (c < N) {
if (leftDist(0, p[c])*2> (lastdist+rightDist(0, p[c]))*2) {
ldir = false;
sum = (lastdist + rightDist(0, p[c])) * 2;
break;
}
else lastdist = leftDist(0, p[c]);
c++;
}
if (ldir) {
if (lastdist < N / 2) sum = lastdist * 2;
else sum = N;
}
}
else {
for (int i = 0; i < N; i++)
{
sum += dist(0,p[i])*2;
}
}
return sum;
}
