Exercise 7: Find Intersection of Multiple Arrays

Problem Statement

Create a function `intersection(...arrays)` that returns common elements in all arrays. Example: intersection([1, 2, 3], [2, 3, 4], [3, 4, 5]) → [3]

Sample Output:

intersection([1, 2, 3], [2, 3, 4], [3, 4, 5]) => [3]
intersection([1, 2], [2, 3], [2, 4]) => [2]

Solution

const intersection = (...arrays) => {
  if (arrays.length === 0) return [];
  return arrays.reduce((acc, arr) => acc.filter(x => arr.includes(x)));
};

Explanation

Overall Goal:

  • Multiple arrays me common elements find karna.

Real world:

  • Data analysis: common items across datasets.
  • Set operations: intersection of multiple sets.