#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define db double
const int N=1e5;
int main () {
ll n; cin>>n;
ll a[n],x;
vector <ll> b;
for(int i=0;i<n;i++) cin>>a[i];
for (int i=0;i<n-1;i++){
x=abs(a[i]-a[i+1]);
b.push_back(x);
}
int k=0;
for (int i=0;i<n;i++) {
// cout<<b[i]<<" ";
if (b[i]>k) k=b[i];
// if (k<a[i]) k=a[i];
}
cout<<k;
return 0;
}
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