#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, max = 0;
  cin >> n;
  int arr[2000000] = {0};
  for (int i = 0; i < n; i++) {
    int temp;
    cin >> temp;
    arr[temp] = temp;
  }
  for (int i = 0; i < 2000000; i++) {
    if (arr[i] == 0 && i > 0) arr[i] = arr[i - 1];
  }
  for (int i = 1; i < 1000000; i++) {
    if (arr[i] == i) {
      for (int j = 2 * i - 1; j < 2000000; j += i) {
        if (max <= arr[j] % i) {
          max = arr[j] % i;
        }
      }
    }
  }
  cout << max << endl;
  return 0;
}

### Prompt

Your task is to create a cpp solution to the following problem:

You are given a sequence a consisting of n integers. Find the maximum possible value of <image> (integer remainder of ai divided by aj), where 1 ≤ i, j ≤ n and ai ≥ aj.

Input

The first line contains integer n — the length of the sequence (1 ≤ n ≤ 2·105). 

The second line contains n space-separated integers ai (1 ≤ ai ≤ 106).

Output

Print the answer to the problem.

Examples

Input

3
3 4 5


Output

2

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, max = 0;
  cin >> n;
  int arr[2000000] = {0};
  for (int i = 0; i < n; i++) {
    int temp;
    cin >> temp;
    arr[temp] = temp;
  }
  for (int i = 0; i < 2000000; i++) {
    if (arr[i] == 0 && i > 0) arr[i] = arr[i - 1];
  }
  for (int i = 1; i < 1000000; i++) {
    if (arr[i] == i) {
      for (int j = 2 * i - 1; j < 2000000; j += i) {
        if (max <= arr[j] % i) {
          max = arr[j] % i;
        }
      }
    }
  }
  cout << max << endl;
  return 0;
}

```