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

int main()
{
    int n;
    cin >> n;
    vector<ll> x(n);
    for (int i = 0; i < n; i++)
        cin >> x[i];
    sort(x.begin(), x.end());
    ll m = 1e9 + 7, M = m;
    for (int i = 1; i < n; i++)
        m = min(m, (x[i] == x[i - 1] ? M : abs(x[i] - x[i - 1])));
    cout << (m == M ? 0 : m) << endl;
}