JavaScript - Find the non-repeated element from an array

JavaScript Bit Manipulation: Exercise-14 with Solution

Non-Repeated Element

In an array every element appears twice except for one. Write a JavaScript program to find the non-repeated element in an array using bit manipulation.

Test Data:
([1]) -> 1
([1, 2, 3]) -> 0 [All elements are non- repeated]
[1, 2, 8, 3, 1, 2, 3, 8, 6, 6, 7] -> 7

Sample Solution:

JavaScript Code:

// Define a function to find the non-repeated number in an array of integers
const non_repeated_num = (nums) => {
   let r = 0; // Initialize a variable to store the result
   // Iterate through the array elements
   for(let i = 0; i <= nums.length; i++) {
       r = r ^ nums[i]; // Use bitwise XOR operation to find the non-repeated number
   }
   return r; // Return the non-repeated number
}

// Define an array of integers
nums = [1, 2, 8, 3, 1, 2, 3, 8, 6, 6, 7];

// Call the non_repeated_num function to find the non-repeated number in the array
console.log(non_repeated_num(nums));

Output:

7

Flowchart:

Live Demo:

See the Pen javascript-bit-manipulation-exercise-14 by w3resource (@w3resource) on CodePen.

* To run the code mouse over on Result panel and click on 'RERUN' button.*

For more Practice: Solve these Related Problems:

• Write a JavaScript function that finds the unique element in an array where every other element appears twice using bitwise XOR.
• Write a JavaScript function that handles arrays where all elements are non-repeated by returning a specific message.
• Write a JavaScript function that iterates through an array and uses XOR to cancel out repeated numbers, returning the non-repeated one.
• Write a JavaScript function that validates the input array and returns an error if it contains non-numeric values.

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