#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define ent "\n"
const int maxn = 2e5 + 100;
const ll INF = (ll)1e18 + 100;
const int inf = 1e9 + 100;
const int MOD = 1e9 + 7;
const int maxl = 30;
const int P = 31;
int n, h;
int a[maxn];
int b[maxn];
void test(){
cin >> n >> h;
for(int i = 1; i <= n; i++){
cin >> a[i];
}
ll ans = INF;
for(int i = 1; i <= n; i++){
for(int j = 1; j <= n; j++){
b[j] = a[j];
}
ll sum = 0;
for(int j = i + 1; j <= n; j++){
if(abs(b[j] - b[j-1]) <= h) continue;
sum += abs(b[j] - b[j-1]) - h;
if(b[j] > b[j-1]){
b[j] = b[j-1] + h;
} else{
b[j] = b[j-1] - h;
}
}
for(int j = i - 1; j > 0; j--){
if(abs(b[j] - b[j+1]) <= h) continue;
sum += abs(b[j] - b[j+1]) - h;
if(b[j] > b[j+1]){
b[j] = b[j+1] + h;
} else{
b[j] = b[j+1] - h;
}
}
ans = min(ans, sum);
}
cout << ans;
}
// 6 1
// 2 10 0 2 4 3
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int t = 1; t = 1;
while(t--) test();
cout << ent;
}
