Some JS script in Array

features.js

1. How Do You Find the Largest Number in an Array?

function findLargest(arr) {
  return Math.max(...arr);
}

console.log(findLargest([1, 5, 3, 9, 2])); // 9

2. How Do You Find the Second Largest Number in an Array?

function secondLargest(arr) {
  let sorted = arr.sort((a, b) => b - a);
  return sorted[1];
}

console.log(secondLargest([1, 5, 3, 9, 7])); // 7

3. How Do You Remove Duplicates from an Array?

function removeDuplicates(arr) {
  return [...new Set(arr)];
}

console.log(removeDuplicates([1, 2, 2, 3, 4, 4, 5])); // [1, 2, 3, 4, 5]

4. How Do You Merge Two Sorted Arrays?

function mergeArrays(arr1, arr2) {
  return arr1.concat(arr2).sort((a, b) => a - b);
}

console.log(mergeArrays([1, 3, 5], [2, 4, 6])); // [1, 2, 3, 4, 5, 6]

5. How Do You Rotate an Array?

function rotateArray(arr, k) {
  k = k % arr.length; // Handle cases where k > array length
  return arr.slice(-k).concat(arr.slice(0, -k));
}

console.log(rotateArray([1, 2, 3, 4, 5], 2)); // [4, 5, 1, 2, 3]

6. How Do You Check if Two Arrays Are Equal?

function arraysEqual(arr1, arr2) {
  if (arr1.length !== arr2.length) return false;
  
  for (let i = 0; i < arr1.length; i++) {
    if (arr1[i] !== arr2[i]) return false;
  }
  
  return true;
}

console.log(arraysEqual([1, 2, 3], [1, 2, 3])); // true
console.log(arraysEqual([1, 2, 3], [1, 2, 4])); // false

7. How Do You Find All Pairs in an Array That Sum to a Specific Value?

function findPairs(arr, target) {
  let result = [];
  let seen = new Set();

  for (let num of arr) {
    let complement = target - num;

    if (seen.has(complement)) {
      result.push([num, complement]);
    }

    seen.add(num);
  }

  return result;
}

console.log(findPairs([2, 4, 3, 5, 7, 8, 9], 10)); // [[7, 3], [8, 2], [9, 1]]

GOOD JOBS. :)))