// Coded by hjxddl
#include <bits/stdc++.h>
#define ll long long
#define db double
const int N = 2e5 + 5;
void solve() {
    ll n, d;
    std::cin >> n >> d;
    std::vector<ll> a(n + 5);
    for (int i = 1; i <= n; i++) {
        std::cin >> a[i];
    }
    ll ans = 0;
    for (int i = 1; i <= n; i++) {
        ll l = a[i], r = a[i] + d;
        ll ans1 = 0;
        for (int j = 1; j < n; j++) {
            ll x, y;
            if (a[j] < l)
                x = l;
            else if (a[j] > r)
                x = r;
            else
                x = a[j];
            if (a[j + 1] < l)
                y = l;
            else if (a[j + 1] > r)
                y = r;
            else
                y = a[j + 1];
            ans1 += std::abs(x - y);
        }
    }
    for (int i = 1; i <= n; i++) {
        ll r = a[i], l = a[i] - d;
        ll ans1 = 0;
        for (int j = 1; j < n; j++) {
            ll x, y;
            if (a[j] < l)
                x = l;
            else if (a[j] > r)
                x = r;
            else
                x = a[j];
            if (a[j + 1] < l)
                y = l;
            else if (a[j + 1] > r)
                y = r;
            else
                y = a[j + 1];
            ans1 += std::abs(x - y);
        }
        ans = std::max(ans, ans1);
    }
    std::cout << ans << '\n';
}
int main() {
    std::ios::sync_with_stdio(0);
    std::cin.tie(0), std::cout.tie(0);
    int t = 1;
    // std::cin >> t;
    while (t--) {
        solve();
    }
    std::cout << std::flush;
}