#include<bits/stdc++.h>
using namespace std;
int n,a[32768],id,l;
long long h;
int main() {
    cin>>n>>h;
    a[1]=h;
    for(int i=2;i<=n;i++){
        cin>>a[i];
        id=i;
        while(a[id]<a[id-1]){
            swap(a[id],a[id-1]);
            id--;
        }
        if(id==1)l=a[id+1]-a[id];
        else if(id==i)l=a[id]-a[id-1];
        else l=min(a[id+1]-a[id],a[id]-a[id-1]);
        h+=l;
    }
    cout<<h;
    return 0;
}