#include <iostream>
#include <algorithm>
#include <climits>
#include <math.h>
using namespace std;
int main(void){
    // Your code here!
    
    int n;
    cin >> n;
    if(n <= 1){
        cout << 0;
        return 0;
    }
    int min = INT_MAX;
    int x[n];
    for(int i = 0; i < n; i++) cin >> x[i];
    
    for(int i = 0; i < n - 1; i++) {
        for(int j = i + 1; j < n; j++) {
            if(x[i] == x[j])continue;
            int ab = abs(x[i] - x[j]);
            if(min > ab)min = ab;
        }
    }
    if(min == INT_MAX)cout << 0;
    else cout << min;
    
    
}