#include<iostream>
#include<vector>
#include<algorithm>
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());
	int c = 1000001;
	for (int i = 0; i < n - 1; i++) {
		if (x[i + 1] != x[i] && x[i + 1] - x[i] < c) {
			c = x[i + 1] - x[i];
		}
	}
	if (c == 1000001) {
		cout << 0 << endl;
	}
	else {
		cout << c << endl;
	}
}