#include <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <iomanip>
#include <algorithm>
using namespace std;
using ll = long long;

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 res = 1e9;
    for(int i=0; i<x.size()-1; ++i) {
        res = min(res, x[i+1]-x[i]);
    }
    cout << (res == 1e9 ? 0 : res) << endl;
}