#include <iostream>
#include <algorithm>
#include <cmath>
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);

    float min = INFINITY,cou = 0;
    for(int i = 0; i < n - 1; i++){
        if(x[i+1] == x[i]) cou++;
        else if(x[i+1] - x[i] < min) min = x[i+1] - x[i];  
    }

    if(n == 1 || cou + 1 == n) cout << '0' << endl;
    else cout << min << endl;

    return 0;
}