#include <algorithm>
#include <iostream>

using namespace std;

int main(int argc, const char* argv[])
{
	int N;
	cin >> N;
	int X[N];
	for (auto&& x : X) cin >> x;
	sort(X, &X[N]);
	int defval = (int)1e6 + 1;
	int minGap = defval;
	for (int i = 1; i < N; i++) {
		int gap				= abs(X[i] - X[i - 1]);
		if (gap > 0) minGap = min(minGap, gap);
	}
	cout << (minGap != defval ? minGap : 0) << endl;
	return 0;
}