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

int main() {
    int N;
    cin >> N;
    vector<int> X(N);
    for (int i = 0; i < N; i++) {
        cin >> X[i];
    }

    sort(X.begin(), X.end());
    X.erase(unique(X.begin(), X.end()), X.end());
    int ans = 1e7;
    for (int i = 0; i < X.size() - 1; i++) {
        ans = min(ans, X[i + 1] - X[i]);
    }
    if (ans == 1e7)
        ans = 0;

    cout << ans << endl;
}