#include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     long long n;     cin >> n;     long long a[n];     for (long long i = 0; i < n; i++) cin >> a[i];     long long f[n - 1];     long long s[n - 1];     for (long long i = 0; i < n - 1; i++) {       f[i] = abs((a[i] - a[i + 1])) * pow(-1, i);       s[i] = abs((a[i] - a[i + 1])) * (pow(-1, i + 1));     }     long long curr = f[0];     long long max_sofar = f[0];     for (long long i = 1; i <= n - 2; i++) {       curr = max(f[i], curr + f[i]);       max_sofar = max(max_sofar, curr);     }     if (n > 2) curr = s[1];     max_sofar = max(max_sofar, curr);     for (long long i = 2; i <= n - 2; i++) {       curr = max(s[i], curr + s[i]);       max_sofar = max(max_sofar, curr);     }     cout << max_sofar;     return 0;   }   