JavaScript: Find the difference of two arrays

Last update on March 03 2025 12:46:17 (UTC/GMT +8 hours)

JavaScript Array: Exercise-23 with Solution

Difference Between Arrays

Write a JavaScript function to find the difference between two arrays.

Test Data:
console.log(difference([1, 2, 3], [100, 2, 1, 10]));
["3", "10", "100"]
console.log(difference([1, 2, 3, 4, 5], [1, [2], [3, [[4]]],[5,6]]));
["6"]
console.log(difference([1, 2, 3], [100, 2, 1, 10]));
["3", "10", "100"]

Visual Presentation:

JavaScript: Find the difference of two arrays

Sample Solution:

JavaScript Code:

// Function to find the difference of two arrays
function differenceOf2Arrays(array1, array2) {
  // Temporary array to store the differences
  var temp = [];

  // Convert array1 to an array of numbers
  array1 = array1.toString().split(',').map(Number);
  
  // Convert array2 to an array of numbers
  array2 = array2.toString().split(',').map(Number);

  // Iterate through each element in array1
  for (var i in array1) {
    // If the element is not found in array2, add it to the temp array
    if (array2.indexOf(array1[i]) === -1)
      temp.push(array1[i]);
  }

  // Iterate through each element in array2
  for (i in array2) {
    // If the element is not found in array1, add it to the temp array
    if (array1.indexOf(array2[i]) === -1)
      temp.push(array2[i]);
  }

  // Return the temp array sorted in ascending order
  return temp.sort((a, b) => a - b);
}

// Output the result of the differenceOf2Arrays function with sample arrays
console.log(differenceOf2Arrays([1, 2, 3], [100, 2, 1, 10]));
console.log(differenceOf2Arrays([1, 2, 3, 4, 5], [1, [2], [3, [[4]]], [5, 6]]));

Output:

[3,10,100]
[6]

Flowchart:

ES6 Version:

// Function to find the difference of two arrays
const differenceOf2Arrays = (array1, array2) => {
  // Temporary array to store the differences
  let temp = [];

  // Convert array1 to an array of numbers
  array1 = array1.toString().split(',').map(Number);
  
  // Convert array2 to an array of numbers
  array2 = array2.toString().split(',').map(Number);

  // Iterate through each element in array1
  for (let i of array1) {
    // If the element is not found in array2, add it to the temp array
    if (array2.indexOf(i) === -1)
      temp.push(i);
  }

  // Iterate through each element in array2
  for (let i of array2) {
    // If the element is not found in array1, add it to the temp array
    if (array1.indexOf(i) === -1)
      temp.push(i);
  }

  // Return the temp array sorted in ascending order
  return temp.sort((a, b) => a - b);
};

// Output the result of the differenceOf2Arrays function with sample arrays
console.log(differenceOf2Arrays([1, 2, 3], [100, 2, 1, 10]));
console.log(differenceOf2Arrays([1, 2, 3, 4, 5], [1, [2], [3, [[4]]], [5, 6]]));

Live Demo:

For more Practice: Solve these Related Problems:

Write a JavaScript function that finds the difference between two arrays, returning elements present in one but not in the other.
Write a JavaScript function that computes the symmetric difference between two arrays using nested filters.
Write a JavaScript function that compares two arrays and returns the items unique to each array.
Write a JavaScript function that performs a deep difference on arrays containing nested arrays.

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