feat(array-methods): add examples for array manipulation methods

- Demonstrated various array methods including push, pop, unshift, shift, slice, and splice with detailed examples.

- Included examples showcasing:
  - Adding and removing elements dynamically using push and pop.
  - Array conversions using 	oString.
  - Merging arrays with concat.
  - Replacing and modifying elements using splice.

- Added a practice scenario involving company names:
  - Removed the first company.
  - Replaced Uber with Ola.
  - Added Amazon at the end.

Author: Harshitap0809

02_Basics/01_Arrays8.js

@@ -0,0 +1,253 @@
+
+// ==========================
+// Array Methods Demonstration
+// ==========================
+
+// ==========================
+// 1. push() : Add to end
+// ==========================
+
+// Initialize an array with food items
+let foodArray = ["chips", "cheese", "bread", "paneer"];
+console.log("Initial foodArray:", foodArray); 
+// Output: Initial foodArray: [ 'chips', 'cheese', 'bread', 'paneer' ]
+
+// Mutates the original array by adding items
+foodArray.push("milk", "onion", "corn-flour");
+console.log("After push:", foodArray); 
+// Output: After push: [ 'chips', 'cheese', 'bread', 'paneer', 'milk', 'onion', 'corn-flour' ]
+
+// Returns the new length of the array
+let updatedLength = foodArray.push("lettuce");
+console.log("New length:", updatedLength); 
+// Output: New length: 8
+
+// Can accept multiple arguments
+foodArray.push("tomato", "cucumber");
+console.log("After pushing more items:", foodArray); 
+// Output: After pushing more items: [ 'chips', 'cheese', 'bread', 'paneer', 'milk', 'onion', 'corn-flour', 'lettuce', 'tomato', 'cucumber' ]
+
+// Handles different data types
+foodArray.push(42, { item: "apple" });
+console.log("After pushing different types:", foodArray); 
+// Output: After pushing different types: 
+// [ 'chips', 'cheese', 'bread', 'paneer', 'milk', 'onion', 'corn-flour', 
+//   'lettuce', 'tomato', 'cucumber', 42, { item: 'apple' } ]
+
+// Can push `undefined`
+foodArray.push(undefined);
+console.log("After pushing undefined:", foodArray); 
+// Output: After pushing undefined: 
+// [ 'chips', 'cheese', 'bread', 'paneer', 'milk', 'onion', 'corn-flour', 
+//   'lettuce', 'tomato', 'cucumber', 42, { item: 'apple' }, undefined ]
+
+// Use in loops to add items
+let additionalItems = ["carrot", "spinach"];
+additionalItems.forEach(item => foodArray.push(item));
+console.log("After pushing items in a loop:", foodArray); 
+// Output: After pushing items in a loop: 
+// [ 'chips', 'cheese', 'bread', 'paneer', 'milk', 'onion', 'corn-flour', 
+//   'lettuce', 'tomato', 'cucumber', 42, { item: 'apple' }, undefined, 
+//   'carrot', 'spinach' ]
+
+
+// ==========================
+// 2. pop() : Delete from end & return
+// ==========================
+
+// Initialize an array of fruits
+let fruitArray = ["apple", "banana"];
+console.log("Initial fruitArray:", fruitArray); 
+// Output: Initial fruitArray: [ 'apple', 'banana' ]
+
+// Use push() to add a single element
+fruitArray.push("orange");
+console.log("After push('orange'):", fruitArray); 
+// Output: After push('orange'): [ 'apple', 'banana', 'orange' ]
+
+// Use push() to add multiple elements
+fruitArray.push("grape", "kiwi");
+console.log("After push('grape', 'kiwi'):", fruitArray); 
+// Output: After push('grape', 'kiwi'): [ 'apple', 'banana', 'orange', 'grape', 'kiwi' ]
+
+// Pushing different data types
+let mixedArray = [1, "two", true];
+mixedArray.push(null, { key: "value" });
+console.log("Mixed array after push:", mixedArray); 
+// Output: Mixed array after push: [ 1, 'two', true, null, { key: 'value' } ]
+
+// Push on an empty array
+let emptyArray = [];
+emptyArray.push(1);
+console.log("Empty array after push(1):", emptyArray); 
+// Output: Empty array after push(1): [ 1 ]
+
+
+// ==========================
+// 3. toString() : Converts array to string
+// ==========================
+
+// Initialize an array of colors
+let colorArray = ["red", "green", "blue"];
+let colorString = colorArray.toString();
+console.log("Array as string:", colorString); 
+// Output: Array as string: red,green,blue
+
+// Handle nested arrays
+let nestedArray = [1, 2, [3, 4], 5];
+console.log("Nested array as string:", nestedArray.toString()); 
+// Output: Nested array as string: 1,2,3
+
+
+
+// ==========================
+// 4. concat() : Merge Arrays
+// ==========================
+
+// Initialize two arrays
+let firstArray = ["a", "b", "c"];
+let secondArray = ["d", "e", "f"];
+console.log("Initial firstArray:", firstArray); 
+// Output: Initial firstArray: [ 'a', 'b', 'c' ]
+console.log("Initial secondArray:", secondArray); 
+// Output: Initial secondArray: [ 'd', 'e', 'f' ]
+
+// Use concat() to merge arrays
+let mergedArray = firstArray.concat(secondArray);
+console.log("Merged array:", mergedArray); 
+// Output: Merged array: [ 'a', 'b', 'c', 'd', 'e', 'f' ]
+
+// Concat with multiple arrays
+let thirdArray = ["g", "h"];
+let combinedArray = firstArray.concat(secondArray, thirdArray);
+console.log("Combined array:", combinedArray); 
+// Output: Combined array: [ 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h' ]
+
+// Concat with different data types
+let mixedConcatArray = firstArray.concat(42, { key: "value" });
+console.log("Mixed array after concat:", mixedConcatArray); 
+// Output: Mixed array after concat: [ 'a', 'b', 'c', 42, { key: 'value' } ]
+
+
+// ==========================
+// 5. unshift() : Add to Beginning
+// ==========================
+
+// Initialize an array of numbers
+let numberArray = [2, 3, 4];
+console.log("Initial numberArray:", numberArray); 
+// Output: Initial numberArray: [ 2, 3, 4 ]
+
+// Use unshift() to add elements to the beginning
+numberArray.unshift(1);
+console.log("After unshift(1):", numberArray); 
+// Output: After unshift(1): [ 1, 2, 3, 4 ]
+
+// Unshift multiple elements
+numberArray.unshift(-1, 0);
+console.log("After unshift(-1, 0):", numberArray); 
+// Output: After unshift(-1, 0): [ -1, 0, 1, 2, 3, 4 ]
+
+// Unshift different data types
+numberArray.unshift("start", null);
+console.log("After unshift('start', null):", numberArray); 
+// Output: After unshift('start', null): [ 'start', null, -1, 0, 1, 2, 3, 4 ]
+
+
+// ==========================
+// 6. shift() : Remove from Beginning & Return
+// ==========================
+
+// Initialize an array of fruits
+let fruitList = ["apple", "banana", "cherry"];
+console.log("Initial fruitList:", fruitList); 
+// Output: Initial fruitList: [ 'apple', 'banana', 'cherry' ]
+
+// Use shift() to remove the first element
+let removedFruit = fruitList.shift();
+console.log("Removed fruit:", removedFruit); 
+// Output: Removed fruit: apple
+console.log("After shift:", fruitList); 
+// Output: After shift: [ 'banana', 'cherry' ]
+
+// Shift again
+let secondRemovedFruit = fruitList.shift();
+console.log("Removed fruit:", secondRemovedFruit); 
+// Output: Removed fruit: banana
+console.log("After another shift:", fruitList); 
+// Output: After another shift: [ 'cherry' ]
+
+// Shift from a single-element array
+fruitList.shift();
+console.log("After shifting the last element:", fruitList); 
+// Output: After shifting the last element: [ ]
+
+// Shift from an empty array
+let emptyList = [];
+let removedFromEmptyList = emptyList.shift();
+console.log("Removed from empty array:", removedFromEmptyList); 
+// Output: Removed from empty array: undefined
+console.log("After shift on empty array:", emptyList); 
+// Output: After shift on empty array: [ ]
+
+// ==========================
+// 7. slice() : Extract and return a portion of an array
+//  slice syntax : slice( startIdx, endIdx )
+// ==========================
+
+// Initialize an array of vegetables
+let vegArray = ["carrot", "potato", "tomato", "onion", "spinach"];
+console.log("Initial vegArray:", vegArray);
+// Output: Initial vegArray: [ 'carrot', 'potato', 'tomato', 'onion', 'spinach' ]
+
+// Use slice() to extract a portion of the array
+let slicedArray = vegArray.slice(1, 3);
+console.log("Sliced array (1, 3):", slicedArray);
+// Output: Sliced array (1, 3): [ 'potato', 'tomato' ]
+
+// Slice without specifying endIdx (extract till end)
+let slicedToEnd = vegArray.slice(2);
+console.log("Sliced from index 2:", slicedToEnd);
+// Output: Sliced from index 2: [ 'tomato', 'onion', 'spinach' ]
+
+// Slice with negative indices
+let slicedNegative = vegArray.slice(-3, -1);
+console.log("Sliced with negative indices (-3, -1):", slicedNegative);
+// Output: Sliced with negative indices (-3, -1): [ 'tomato', 'onion' ]
+
+// Original array remains unchanged
+console.log("After slice, original array:", vegArray);
+// Output: After slice, original array: [ 'carrot', 'potato', 'tomato', 'onion', 'spinach' ]
+
+
+// ==========================
+// 8. splice() : Modify original array (add, remove, or replace)
+// syntax : splice( startIdx, delCount, newElm...)
+// ==========================
+
+// Initialize an array of fruits
+let fruitBasket = ["apple", "banana", "cherry", "date"];
+console.log("Initial fruitBasket:", fruitBasket);
+// Output: Initial fruitBasket: [ 'apple', 'banana', 'cherry', 'date' ]
+
+// Use splice() to remove elements
+let removedFruits = fruitBasket.splice(1, 2); // Remove 2 elements starting at index 1
+console.log("Removed fruits:", removedFruits);
+// Output: Removed fruits: [ 'banana', 'cherry' ]
+console.log("After removing fruits:", fruitBasket);
+// Output: After removing fruits: [ 'apple', 'date' ]
+
+// Use splice() to add elements
+fruitBasket.splice(1, 0, "blueberry", "grape"); // Add at index 1 without removing
+console.log("After adding fruits:", fruitBasket);
+// Output: After adding fruits: [ 'apple', 'blueberry', 'grape', 'date' ]
+
+// Use splice() to replace elements
+fruitBasket.splice(2, 1, "kiwi"); // Replace 1 element at index 2
+console.log("After replacing an element:", fruitBasket);
+// Output: After replacing an element: [ 'apple', 'blueberry', 'kiwi', 'date' ]
+
+// Use splice() to clear all elements
+fruitBasket.splice(0, fruitBasket.length);
+console.log("After clearing all elements:", fruitBasket);
+// Output: After clearing all elements: []