#include <bits/stdc++.h>
using namespace std;

int main(){
	int n;
	cin >> n;
	vector<long long> data(n);
	long long ans = LLONG_MAX;
	for(auto &a:data) cin >> a;
	sort(data.begin(),data.end());
	data.erase(unique(data.begin(),data.end()),data.end());
	for(int i = 0; i < n - 1; i++){
		int j = i + 1;
		if(data[i] == data[j]) continue;
		else ans = min(ans,abs(data[i] - data[j]));
	}
	cout << (ans == LLONG_MAX ? 0 : ans) << endl;
	return 0;
}