#include<iostream>
#include<numeric>
#include<vector>
#include<algorithm>

int main() {
	int num;
	std::cin >> num;

	std::vector<int> v(num);

	for (int i = 0; i < num; i++) {
		std::cin >> v[i];
	}

	std::sort(v.begin(), v.end());
	v.erase(std::unique(v.begin(), v.end()), v.end());

	std::vector<int> r(v.size());
	std::adjacent_difference(v.begin(), v.end(), r.begin());

	r.erase(r.begin());
	for (size_t i = 0; i < r.size(); i++) {
		r[i] = abs(r[i]);
	}

	std::cout << *std::min_element(r.begin(), r.end()) << std::endl;
	return 0;
}