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

int main()
{
    int n;
    cin >> n;

    int x[n];
    for(int i = 0; i < n; i++)
        cin >> x[i];
    
    sort(x,x+n);

    int min = 100000000,cou = 0;
    for(int i = 1; i < n; i++){
        if(x[i] - x[i-1] < min && x[i] != x[i-1]) min = x[i] - x[i-1];
        if(x[i] == x[i-1]) cou++;
    }

    cout << ((n == 1 || n == cou + 1) ? 0 : min) << endl;

    return 0;
}