#include <bits/stdc++.h>
using namespace std;

using ll=long long;
ll mod=1000000007;
ll INF=1LL<<60;

int main() {
	int N;
	cin >> N;
	set<int> X;
	for(int i=0;i<N;i++){
		int A;
		cin >> A;
		X.insert(A);
	}
	int ans=1000000000;;
	for(auto it=X.begin();it!=prev(X.end());it++){
		int A=(*it);
		int B=*next(it);
		ans=min(ans,B-A);
	}
	if(ans==1000000000){
		cout << 0 << endl;
		return 0;
	}
	cout << ans << endl;
}