#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}
#define MAX_N 200005

int main() {
    int n;
    cin >> n;
    int x[n];
    rep(i,n)cin >> x[i];
    sort(x,x+n);
    int ans = 1001001001;

    rep(i,n-1){
        if(x[i+1] - x[i] > 0){
            ans = min(ans, x[i+1] - x[i]);
        }
    }

    if(ans > 1001001)ans = 0;

    cout << ans << endl;
    return 0;
}