#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; ++i)
using ll = long long;
using namespace std;
const int INF = 1e9;

int main() {
    int N;
    set<int> st;

    cin >> N;
    rep(i, N) {
        int a;
        cin >> a;
        st.insert(a);
    }

    vector<int> x;
    for (auto s : st)
        x.push_back(s);

    int ans = INF;
    rep(i, x.size() - 1)
        ans = min(ans, x[i + 1] - x[i]);

    ans == INF ? cout << 0 : cout << ans;
    cout << endl;

    return 0;
}