#include <iostream>
#include <algorithm>
using namespace std;

int main()
{
	int N, X[100000];
	int answer = 1000001;

	cin >> N;
	for(int i = 0; i < N; ++i)
	{
		cin >> X[i];
	}

	sort(X, X + N);

	for(int i = 1; i < N; ++i)
	{
		if(X[i] != X[i - 1])
		{
			if(answer > (X[i] - X[i - 1]))
			{
				answer = (X[i] - X[i - 1]);
			}
		}
	}

	if(answer == 1000001)
	{
		answer = 0;
	}

	cout << answer << endl;
	return 0;
}