#include<bits/stdc++.h>
#define fi first
#define se second
#define MULT_TEST 0
using namespace std;
typedef long double ldb;
typedef unsigned long long ull;
const int INF = 0x3f3f3f3f;
const int MOD = 998244353;
const int N = 5005;
int a[N], b[N];
inline int read() {
    int w = 0, f = 1;
    char ch = getchar();
    while (ch < '0' || ch > '9') {
        if (ch == '-') f = -1;
        ch = getchar();
    }
    while (ch >= '0' && ch <= '9') {
        w = (w << 1) + (w << 3) + ch - 48;
        ch = getchar();
    }
    return w * f;
}
int n, d;
inline int Calc(int l, int r) {
    int ans = 0;
    for (int i = 1; i <= n; i++) {
        if (a[i] < l) b[i] = l; 
        else if (a[i] > r) b[i] = r;
        else b[i] = a[i];
    }
    for (int i = 1; i < n; i++) ans += abs(b[i] - b[i + 1]);
    return ans;
}
inline void Solve() {
    n = read(), d = read();
    for (int i = 1; i <= n; i++) a[i] = read();
    int ans = 0;
    for (int i = 1; i <= n; i++) {
        ans = max(ans, Calc(a[i], a[i] + d));
        ans = max(ans, Calc(a[i] - d, a[i]));
    }
    printf("%lld\n", ans);
}
signed main() {
    int _ = 1;
#if MULT_TEST
    _ = read();
#endif 
    while (_--) Solve();
    return 0;
}
/*
8 3
3 1 4 1 5 9 2 6
*/