JavaScript - Check if an Item Exists in a Multidimensional Array

item-exists-in-array.js

const multiArray = [
  [1, 2, 3],
  [4, 5, 6],
  [7, 8, 9]
];

function itemExists(array, item) {
  for (let i = 0; i < array.length; i++) {
    for (let j = 0; j < array[i].length; j++) {
      if (array[i][j] === item) {
        return true;
      }
    }
  }
  return false;
}

console.log(itemExists(multiArray, 5)); // Output: true
console.log(itemExists(multiArray, 10)); // Output: false

////////////////////////////////

const itemToFind = 5;

const exists = multiArray.some(subArray => subArray.includes(itemToFind));
console.log(exists); // Output: true

////////////////////////////////

const itemToFind = 5;

const flattenedArray = multiArray.flat();
const exists = flattenedArray.includes(itemToFind);
console.log(exists); // Output: true

////////////////////

function deepSearch(array, item) {
  for (const element of array) {
    if (Array.isArray(element)) {
      if (deepSearch(element, item)) {
        return true;
      }
    } else if (element === item) {
      return true;
    }
  }
  return false;
}

console.log(deepSearch(multiArray, 5)); // Output: true
console.log(deepSearch(multiArray, 10)); // Output: false