#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    int n, ans = 1e9;
    cin >> n;
    vector<int> xs;
    for (int i = 0; i < n; i++) {
        int x;
        cin >> x;
        xs.push_back(x);
    }
    sort(xs.begin(),xs.end());
    for (int i = 1; i < n; i++) {
        if (xs[i] != xs[i-1])
            ans = min(ans, xs[i]-xs[i-1]);
    }
    if (ans == 1e9)
        ans = 0;
    cout << ans << endl;
    return 0;
}