No_1346.cs

/*
Given an array arr of integers, check if there exist two indices i and j such that :

i != j
0 <= i, j < arr.length
arr[i] == 2 * arr[j]
 

Example 1:

Input: arr = [10,2,5,3]
Output: true
Explanation: For i = 0 and j = 2, arr[i] == 10 == 2 * 5 == 2 * arr[j]
Example 2:

Input: arr = [3,1,7,11]
Output: false
Explanation: There is no i and j that satisfy the conditions.
 

Constraints:

2 <= arr.length <= 500
-103 <= arr[i] <= 103
*/

namespace LeetCode
{
    public class No_1346{
        public bool CheckIfExist(int[] arr)
        {
            for (int i = 0; i < arr.Length - 1; i++)
            {
                for (int j = i + 1; j < arr.Length; j++)
                {
                    if (arr[i] == arr[j] * 2 || arr[i] * 2 == arr[j])
                        return true;
                }
            }
            return false;
        }
    }
}