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

int main() {
  int n;
  std::cin >> n;
  std::vector<int> list(n);
  for (auto &x: list) {
    std::cin >> x;
  }

  std::sort(list.begin(), list.end());
  auto result  = std::unique(list.begin(), list.end());
  // std::for_each(list.begin(), result, [](int x){std::cout << x << " ";});

  int min = 0;
  int pre = -1;
  bool same = false;
  std::for_each(list.begin(), result, [&](int x){
    if (pre != -1) {
      if (min == 0) {
        min = x - pre;
        same = false;
      } else if (x - pre == min) {
        same = true;
      } else if (x - pre < min) {
        min = x - pre;
        same = false;
      }
    }
    pre = x;
  });
  // if (same) {
  //   min = 0;
  // }

  std::cout << min << std::endl;
  return 0;
}