#include <algorithm>
#include <iostream>
#include <iomanip>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <cmath>
using namespace std;

#define FOR(i,s,e) for (int i = int(s); i != int(e); i++)
#define FORIT(i,c) for (typeof((c).begin()) i = (c).begin(); i != (c).end(); i++)
#define ISEQ(c) (c).begin(), (c).end()

int main(){
	int N;
	cin >> N;
	int X[N];
	FOR(i,0,N) cin >> X[i];
	sort(X,X+N);
	int min = 1000001;
	FOR(i,1,N){
		if(X[i-1]!=X[i] && min > X[i]-X[i-1]){
			min = X[i]-X[i-1];
		}
	}

	if(min == 1000001) min = 0;
	cout << min << endl;
	return 0;
}