#include <iostream>
#include <vector>
#include <cmath> 

int main() {
    int n; 
    std::cin >> n;
    
    std::vector<int> distances(n);
    for (int i = 0; i < n; ++i) {
        std::cin >> distances[i];
    }
    
    int max_distance = 0; 
    for (int i = 1; i < n; ++i) {
        int distance = std::abs(distances[i] - distances[i - 1]); 
        if (distance > max_distance) { 
            max_distance = distance;
        }
    }
    std::cout << max_distance << std::endl;
    
    return 0;
}