#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstring>
#include<string>
#include<vector>
#include<queue>
#include<utility>
#include<set>
#include<map>
#include<cctype>
#include<cmath>
#include<algorithm>
using namespace std;

#define RALL(x) (x).rbegin(),(x).rend()
#define ALL(x) (x).begin(),(x).end()
#define repp(i,n) for(int (i)=1;(i)<=(n);(i)++)
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define rev(i,n) for(int (i)=(n-1);(i)>=0;(i)--)
#define EACH(itr,c) for(__typeof((c).begin()) itr=(c).begin(); itr!=(c).end(); itr++)
#define clr(a) memset((a), 0 ,sizeof(a))

typedef pair<int,int> P;
typedef vector<pair<int,int> > pii;
typedef map<string,string> mi;


int main(){
	int n,sum,m=1<<30;
	cin >> n;
	vector<int> vc(n);
	rep(i,n) cin >> vc[i];
	sort(ALL(vc));
	vc.erase(unique(ALL(vc)),vc.end());
	
	if(vc.size()==1){
		cout << 0 << endl;
		return 0;
	}
	
	rep(i,vc.size()-1)
		m=min(m,vc[i+1]-vc[i]);
	
	if(m==1<<30)m=0;
	cout << m << endl;
	return 0;
}