#include <iostream>
#include <sstream>
#include <math.h>
#include <stack>
#include <set>
#include <algorithm>
#include <string>
#include <queue>
#include <stack>
#include <map>
#include <cstdio>
#include <vector>
using namespace std;

#define INF (1 << 30)
#define INFLL (1LL << 60)

int x[1000010];
int main() {
	int n;
	int ans = INF;
	cin >> n;
	for(int i = 0;i < n;i++){
		cin >> x[i];
	}
	for(int i = 0;i < n;i++){
		for(int j = 0;j < n;j++){
			if(i == j)continue;
			if(x[i] == x[j]) continue;
			ans = min(ans,abs(x[i]-x[j]));
		}
	}
	cout << ans << endl;
	return 0;
}