#include <bits/stdc++.h>

using namespace std;

int X[100000];

int main()
{
    int N; cin>>N;
    if (N == 1) {
        cout << 0 << endl;
        return 0;
    }
    for(int i = 0; i < N; ++i) cin >> X[i];
    int mi =1e9;
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < i; ++j) {
            if (X[i]==X[j]) continue;
            mi = min(mi, abs(X[i]-X[j]));
        }
    }
    cout << mi << endl;
}