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

#define FORR(i,b,e) for(int i=(b);i<(int)(e);++i)
#define FOR(i,e) FORR(i,0,e)
#define dump(var) cerr << #var ": " << var << "\n"
#define dumpc(con) for(auto& e: con) cerr << e << " "; cerr<<"\n"

typedef long long ll;
typedef unsigned long long ull;

const double EPS = 1e-6;
const int d4[] = {0, -1, 0, 1, 0};

using namespace std;


int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    int N;
    cin >> N;
    vector<int> x(N);
    FOR(i, N) {
        cin >> x[i];
    }
    sort(x.begin(), x.end());
    x.erase(unique(x.begin(), x.end()), x.end());

    int mx = 1e7;
    FORR(i, 1, x.size()) {
        mx = min(mx, x[i]-x[i-1]);
    }

    cout << (mx==1e7? 0: mx) << endl;
    
    return 0;
}