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

<ul>
	<li><code>i != j</code></li>
	<li><code>0 &lt;= i, j &lt; arr.length</code></li>
	<li><code>arr[i] == 2 * arr[j]</code></li>
</ul>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> arr = [10,2,5,3]
<strong>Output:</strong> true
<strong>Explanation:</strong> For i = 0 and j = 2, arr[i] == 10 == 2 * 5 == 2 * arr[j]
</pre>

<p><strong class="example">Example 2:</strong></p>

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

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>2 &lt;= arr.length &lt;= 500</code></li>
	<li><code>-10<sup>3</sup> &lt;= arr[i] &lt;= 10<sup>3</sup></code></li>
</ul>

class Solution:
    def checkIfExist(self, arr: List[int]) -> bool:
        c =0
        len_arr = len(arr)
        double_counter = 0 
        base_list =[]
        zero_list =[]

        if len_arr <2:
            return False 
        

        else: 
            while (double_counter < 1) and (c < (len_arr-1)) and (len(zero_list) <2):
                for i in range(len_arr):
                    c +=1
                    arr_i = arr[i]
 
                    if arr_i ==0:
                        zero_list.append(arr_i) 
                        base_list.append(arr_i)
                        print(zero_list)

                    if arr_i not in base_list:
                        base_list.append(arr_i)
                        half_store = arr_i/ 2
                        double_store = arr_i*2
                        if (half_store in base_list) or (double_store in base_list):
                            double_counter +=1

            if (double_counter >=1) or (len(zero_list) >=2):
                return True 
            else: 
                return False 
                    
        
# print(f_1(arr))

118