#include <iostream>
#include <algorithm>
#include <vector>

constexpr int INF = 1 << 30;

void solve() {
    int n;
    std::cin >> n;

    std::vector<int> xs(n);
    for (auto& x : xs) std::cin >> x;

    std::sort(xs.begin(), xs.end());
    xs.erase(std::unique(xs.begin(), xs.end()), xs.end());

    int d = INF;
    for (int i = 0; i + 1 < (int)xs.size(); ++i) {
        d = std::min(d, xs[i + 1] - xs[i]);
    }

    std::cout << (d == INF ? 0 : d) << std::endl;
}

int main() {
    std::cin.tie(nullptr);
    std::cout.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}