#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>

using namespace std;

const int INF = 1e9;

void show(vector<int> &a) {
	for (auto it = a.begin(); it != a.end(); it++) {
		cout << *it << " ";
	}
	cout << endl;
}

int main() {
	int n;

	cin >> n;
	vector<int> x(n);
	for (int i = 0; i < n; i++) {
		cin >> x[i];
	}
	sort(x.begin(), x.end());

	// show(x);
	// auto ret = unique(x.begin(), x.end());
	// show(x);
	// x.erase(ret, x.end());
	// show(x);
	x.erase(unique(x.begin(), x.end()), x.end());

	int ans = INF;
	for (int i = 1; i < x.size(); i++) {
		int diff = x[i] - x[i - 1];
		if (diff != 0) {
			ans = min(diff, ans);
		}
	}

	if (ans == INF) {
		ans = 0;
	}
	cout << ans << endl;
	return 0;
}