#include<iostream>
#include<vector>
#include<algorithm>
#define REP(i,a) for(i=0;i<a;i++)

using namespace std;

int main() {
    int n;
    cin>>n;
    vector<int> v;
    int i,x;
    REP(i,n){
      cin>>x;
      v.push_back(x);
    }
    sort(v.begin(),v.end());
    int min=1000000;
    REP(i,v.size()-1){
        if((v[i]!=v[i+1])&&(min>v[i+1]-v[i])){min=v[i+1]-v[i];}
    }
    cout << (min==1000000?0:min) << endl;
    return 0;
}