#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <deque>
#include <math.h>
#define rep(i, s, e) for (ll i = s; i < e; i++)
#define upmax(a, b) a = max(a, b)
#define upmin(a, b) a = min(a, b)
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using pll = pair<ll, ll>;
using vpll = vector<pll>;
using vvpll = vector<vpll>;
const ll INF = 1e18;
const ll MOD = 1e9 + 7;
//const ll MAX_H = 5005;
void solve() {
ll n, H;
cin >> n >> H;
vll arr(n);
rep(i, 0, n) cin >> arr[i];
ll MAX_H = 2 * (*(max_element(arr.begin(), arr.end())));
vll dp(MAX_H, INF);
rep(j, 0, MAX_H) {
dp[j] = abs(arr[0] - j);
}
rep(i, 1, n) {
vll nextdp(MAX_H, INF);
deque<pll> dq;
rep(k, 0, min(MAX_H, H + 1)) {
while (!dq.empty() && dq.back().first > dp[k]) dq.pop_back();
dq.push_back({ dp[k], k });
}
/*multiset<ll> s;
rep(k, 0, min(MAX_H, H + 1)) {
s.insert(dp[k]);
}
nextdp[0] = *s.begin() + abs(arr[i]);*/
rep(j, 1, MAX_H) {
if (j + H < MAX_H) {
while (!dq.empty() && dq.back().first > dp[j + H]) dq.pop_back();
dq.push_back({ dp[j + H], j + H });
}
nextdp[j] = dq.front().first + abs(arr[i] - j);
if (dq.front().second <= j - H) {
dq.pop_front();
}
/*if (j + H < MAX_H) {
s.insert(dp[j + H]);
}
nextdp[j] = *(s.begin()) + abs(arr[i] - j);
if (j - H >= 0) {
auto it = s.find(dp[j - H]);
s.erase(it);
}*/
}
swap(nextdp, dp);
}
ll res = INF;
rep(j, 0, MAX_H) upmin(res, dp[j]);
cout << res << endl;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
solve();
}
