All DSA Topics in JavaScript

// Data structure: Array
const numbers = [1, 2, 3, 4, 5];

// Algorithm: Linear search
function findNumber(array, number) {
  for (let i = 0; i < array.length; i++) {
    if (array[i] === number) {
      return i;
    }
  }

  return -1;
}

// Find the index of the number 3 in the array
const index = findNumber(numbers, 3);

// If the index is not equal to -1, then the number was found
if (index !== -1) {
  console.log(`The number ${numbers[index]} was found at index ${index}`);
} else {
  console.log('The number was not found in the array');
}