#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ld,ld> pdd;
#define ff(i,a,b) for(int i = a; i <= b; i++)
#define fb(i,b,a) for(int i = b; i >= a; i--)
#define trav(a,x) for (auto& a : x)
#define sz(a) (int)(a).size()
#define pb push_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k) print the k-th smallest number in os(0-based)
const int mod = 1000000007;
const ll inf = 1e18 + 5;
const int mxN = 200005;
int n, K, L;
int niz[mxN];
ll dp[mxN];
ll delivery(int _N, int _K, int _L, int positions[]){
n = _N; K = _K; L = _L; ff(i,1,n)niz[i] = positions[i - 1];
ff(i,1,n)dp[i] = inf;
int pola = L / 2 + 1;
dp[0] = 0;
ff(i,1,n){
int M = 0, V = 0;
fb(j,i,max(1,i - K + 1)){
if(niz[j] < pola)M = max(M, niz[j]);
if(niz[j] >= pola)V = max(V, niz[j]);
if(M != 0 && V != 0)dp[i] = min(dp[i], dp[j - 1] + L);
else if(M != 0)dp[i] = min(dp[i], dp[j - 1] + 2ll * M);
else dp[i] = min(dp[i], dp[j - 1] + 2ll * (L - V));
}
}
return dp[n];
}
// int main() {
// cin.tie(0)->sync_with_stdio(0);
// int _N, _K, _L;
// cin >> _N >> _K >> _L;
// int A[_N];
// ff(i,0,_N - 1)cin >> A[i];
// cout << delivery(_N, _K, _L, A) << '\n';
// return 0;
// }
/*
3 2 8
1 2 5
// probati bojenje sahovski
*/
