#include <iostream>	//cin, cout
#include <vector>	//vector
#include <algorithm> //sort,min,max
#include <string>	//string
#include <ios>		//fixed
#include <iomanip>	//setprecision
#include <utility> //swap
#include <cstdlib>	//abs(int)
#include <cmath>	//sqrt
#include <sstream>	//stringstream,getline

using namespace std;

int main() {

	int N;
	cin >> N;

	if (N == 1) {
		cout << 0 << endl;
		return 0;
	}

	vector<int> X(N);
	for (int i = 0; i < N; i++) {
		cin >> X[i];
	}

	sort(X.begin(), X.end());

	int min = 1000001;
	int temp = 0;
	for (int i = 1; i < N; i++) {
		temp = X[i] - X[i - 1];
		if (temp != 0) {
			if (temp < min) {
				min = temp;
			}
		}
	}

	if (min == 1000001) {
		cout << 0 << endl;
	}
	else {
		cout << min << endl;
	}

	return 0;

}