#include <bits/stdc++.h>

using namespace std;

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());
	x.erase(unique(x.begin(), x.end()), x.end());

	if (x.size() >= 2) {
		int ans = 1e9;
		for (int i = 0; i < x.size()-1; ++i) {
			ans = min(ans, x[i+1]-x[i]);
		}
		cout << ans << endl;
	}
	else {
		cout << 0 << endl;
	}
}