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HTML

              
                <h1>Paireds and Unpaireds</h1>
              
            
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CSS

              
                
              
            
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JS

              
                /*
INSTRUCTIONS:
- You have 1 hour to complete the task.
- You will be recorded, so please remember to explain the code you do.
- Starting by the design of your solution is a good approach. Don't jump into code immediatly.
- Since no one will resolve questions while you are coding, make assumptions and explain them.
- Once you complete the code, please send it by email to the person guiding your session.
- You can use console (F12) to check your results

DESCRIPITION:
An array consisting of integers is given. Each element of the array can be paired with another element that has the same value, except for one element that is left unpaired.

For example, in array such this: [1, 2, 2]
Elements at indexes 1 and 2 are paired
Element at index 0 has value 1 and is unpaired.

Write a function:
function findUnpairElement(array)

It will return 1 for the sample above. 

* Unexpected things might happen, you should decide what to do if the Array contains invalid data.*

Array size range is 0..1,000,000, this means:
Array might have no data
Array might have up to 1 million elements, therefore performance is key in your solution.

*/


/*
 * @param array - Array with Paireds and Unpaired (and maybe some unexpected stuff)
 * @returns {number} Unpaired Element
 */
function findUnpairElement(array){

	// In case is not an Array
	if (!Array.isArray(array)) return false;

  return (array).reduce((a, b) => a ^ b);

}

console.log(findUnpairElement([1,2,2]));
console.log(findUnpairElement()); //what about this case? keep it in mind
console.log(findUnpairElement('I dont belong here')); //what about this case? keep it in mind

              
            
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999px

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