#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <climits>
using namespace std;

#define INF INT_MAX/3
#define LINF LLONG_MAX/3

int main(){
	long long N; cin >> N;
	vector<long long> X(N);
	for (int i = 0; i < N; i++) cin >> X[i];
	if (N == 1){
		cout << 0 << endl;
		return 0;
	}
	long long ret = LINF;
	for (int i = 0; i < N - 1; i++){
		if (X[i + 1] - X[i] == 0) continue;
		ret = min(ret, abs(X[i + 1] - X[i]));
	}
	cout << ret << endl;
	return 0;
}