#include<bits/stdc++.h>
#define ll long long
#define fi first
#define se second
using namespace std;
const int nmax = 200002;
ll S[nmax];
ll dp[5005][5005];
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
ll n,h;
deque<pair<ll,ll>>dq;
cin >> n >> h;
for(int i=1;i<=n;i++)cin >> S[i];
for(int i=0;i<=5000;i++)dp[1][i] = abs(S[1] - i);
for(int i=2;i<=n;i++){
dq.clear();
for(int j=0;j<=min(5000ll, h);j++){
while(!dq.empty() && dq.back().fi > dp[i-1][j])dq.pop_back();
dq.push_back({dp[i-1][j], j});
}
for(int j=0;j<=5000;j++){
if(!dq.empty() && dq.front().se < j - h)dq.pop_front();
pair<ll,ll> tmp = dq.front();
dp[i][j] = tmp.fi + abs(S[i] - j);
if(j + h + 1 <= 5000){
while(!dq.empty() && dq.back().fi > dp[i-1][j + h + 1])dq.pop_back();
dq.push_back({dp[i-1][j+h+1], j+h+1});
}
}
}
ll ans = 1e18;
for(int i=0;i<=5000;i++)ans = min(ans, dp[n][i]);
cout << ans;
return 0;
}
