#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <climits>
#include <set>
using namespace std;


bool fnComp (int lhs, int rhs) {return lhs<rhs;}

int main() { 
    int n = 0;
    cin>>n;
    
    bool(*fnPtr)(int,int) = fnComp;
    std::set<int,bool(*)(int,int)> s(fnPtr);
    
    int val;
    for (int i=0; i<n; i++) {
        cin>>val;
        if (s.count(val)) {
            cout<<0;
            return 0;
        }
        s.insert(val);
    }
    
    int min = INT_MAX;
    int cur = 0;
    for (auto it = s.cbegin(); it != std::prev(s.cend()); it++) {
        auto next = std::next(it);
        cur = abs(*next - *it);
        if (cur < min)
            min = cur;
        
    }
    
    cout<<min;
    
    return 0;
}