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

using namespace std;

const int INF = 1e9;

template <class T>
void show(T &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];
	}
	// show(x);
	set<int> y(x.begin(), x.end());
	// show(y);

	int ans = INF;
	auto it = y.begin();
	int prev = *it;
	it++;
	while (it != y.end()) {
		int diff = *it - prev;
		if (diff != 0) {
			ans = min(diff, ans);
		}
		prev = *it;
		it++;
	}

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