#ifdef NYAOWO
#include "grader.cpp"
#endif
#include "boxes.h"
#include <bits/stdc++.h>
#define For(i, a, b) for(int i = a; i <= b; i++)
#define Forr(i, a, b) for(int i = a; i >= b; i--)
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define sz(x) ((int)x.size())
#define eb emplace_back
#define int LL
using namespace std;
using LL = long long;
using pii = pair<int, int>;
const int MAXN = 1000;
const int INF = 1'000'000'000'000'000'000;
int a[MAXN + 10];
int c[MAXN + 10];
int dp[MAXN + 10];
int cost(int l, int r) {
return a[r] - a[l] + c[l] + c[r];
}
long long delivery(int32_t N, int32_t K, int32_t L, int32_t pos[]) {
For(i, 1, N) {
a[i] = pos[i - 1];
c[i] = min(a[i], L - a[i]);
}
dp[0] = 0;
For(i, 1, N) {
dp[i] = INF;
For(j, 1, K) if(i >= j) {
dp[i] = min(dp[i], dp[i - j] + cost(i - j + 1, i));
}
}
return dp[N];
}
