#include <bits/stdc++.h>
using namespace std;
int const N=2e5+3;
int a[N],n,d;
typedef long long ll;
vector <int> val;
ll MAX=-0x3f3f3f3f3f3f3f3f,MIN=-MAX;
pair<int,int> b[N];
ll check(ll l)
{
    int r=l+d;
    long long cnt=0,last=a[1];
    if(a[1]<l) last=l;
    if(a[1]>r) last=r;
    for(int i=2;i<=n;++i)
    {
        int t=a[i];
        if(t<l) t=l;
        if(t>r) t=r;
        cnt+=abs(t-last);
        last=t;
    }
    return cnt;
}
ll solve(ll l,ll r)
{
    if(r-l<=3)
    {
        ll ans=0;
        for(ll i=l;i<=r;++i) ans=max(ans,check(i));
        return ans;
    }
    ll mid=(l+r)>>1,l1=max(l,mid-1),l2=min(r,mid+1),cl=check(l1),cr=check(l2);
    if(cl>cr) return solve(l,l2);
    else return solve(l1,r);
    return 0;
}
priority_queue <int,vector<int>,greater<int> > q;
inline void solve1()
{
    sort(b+1,b+n);
    sort(val.begin(),val.end());
    val.erase(unique(val.begin(),val.end()),val.end());
    long long cnt=0;
    int i=1;
    for(auto l:val)
    {
        int r=l+1;
        while(!q.empty() && q.top()<=l) q.pop();
        while(i<n && b[i].first<r) q.push(b[i].second),i++;
        cnt=max(cnt,(ll)q.size());
    }
    while(!q.empty()) q.pop();
    i=1;
    for(auto r:val)
    {
        int l=r-1;
        while(!q.empty() && q.top()<=l) q.pop();
        while(i<n && b[i].first<r) q.push(b[i].second),i++;
        cnt=max(cnt,(ll)q.size());
    }
    printf("%lld\n",cnt);
}
inline void solve0()
{
    sort(val.begin(),val.end());
    val.erase(unique(val.begin(),val.end()),val.end());
    long long ans=0;
    for(int l:val)
    {
        long long r=l+d;
        if(r>MAX) break;
        long long cnt=0,last=a[1],t;
        if(a[1]<l) last=l;
        if(a[1]>r) last=r;
        for(int i=2;i<=n;++i)
        {
            int t=a[i];
            if(t<l) t=l;
            if(t>r) t=r;
            cnt+=abs(t-last);
            last=t;
        }
        ans=max(ans,cnt);
    }
    for(int r:val)
    {
        long long l=r-d;
        if(r>MAX) break;
        long long cnt=0,last=a[1],t;
        if(a[1]<l) last=l;
        if(a[1]>r) last=r;
        for(int i=2;i<=n;++i)
        {
            int t=a[i];
            if(t<l) t=l;
            if(t>r) t=r;
            cnt+=abs(t-last);
            last=t;
        }
        ans=max(ans,cnt);
    }
    printf("%lld\n",ans);
    exit(0);
}
int main()
{
    scanf("%d%d",&n,&d);
    for(int i=1;i<=n;++i) 
    {
        scanf("%d",&a[i]);
        val.push_back(a[i]);
        MIN=min(MIN,(ll)(a[i]-d)),MAX=max(MAX,1ll*a[i]);
    }
    for(int i=1;i<n;++i) b[i]={min(a[i],a[i+1]),max(a[i],a[i+1])};
    int ll=MIN,rr=MAX;
    if(n<=1000) solve0();
    if(d==1) solve1();
    else printf("%lld\n",solve(ll,rr));
    return 0;
}