অ্যারে (Arrays)

// Creating arrays
let fruits = ["আম", "জাম", "কাঁঠাল"];
let mixed = [42, "hello", true, null, [1, 2, 3]];
let empty = [];

// Accessing by index (starts at 0!)
console.log(fruits[0]);   // "আম"
console.log(fruits[2]);   // "কাঁঠাল"
console.log(fruits[99]);  // undefined (no error, just undefined)

// .at() supports negative indexes
console.log(fruits.at(-1)); // "কাঁঠাল" (last item)
console.log(fruits.at(-2)); // "জাম" (second to last)

// .length — how many items
console.log(fruits.length);  // 3

// Changing a value
fruits[1] = "blueberry";
console.log(fruits); // ["আম", "blueberry", "কাঁঠাল"]

আম
cherry
undefined
cherry
banana
3
["আম", "blueberry", "কাঁঠাল"]

let queue = ["Anika", "Rafi"];

// push — add to end
queue.push("Sadia");
console.log(queue); // ["Anika", "Rafi", "Sadia"]

// pop — remove from end
let last = queue.pop();
console.log(last);  // "Sadia"
console.log(queue); // ["Anika", "Rafi"]

// unshift — add to front
queue.unshift("Zara");
console.log(queue); // ["Zara", "Anika", "Rafi"]

// shift — remove from front
let first = queue.shift();
console.log(first); // "Zara"
console.log(queue); // ["Anika", "Rafi"]

// splice — insert at index 1, remove 0 items, add "Esha"
queue.splice(1, 0, "Esha");
console.log(queue); // ["Anika", "Esha", "Rafi"]

// splice — remove 1 item at index 1
queue.splice(1, 1);
console.log(queue); // ["Anika", "Rafi"]

["Anika", "Rafi", "Sadia"]
Charlie
["Anika", "Rafi"]
["Zara", "Anika", "Rafi"]
Zara
["Anika", "Rafi"]
["Anika", "Esha", "Rafi"]
["Anika", "Rafi"]

// Spread — copy an array (not a reference!)
let original = [1, 2, 3];
let copy = [...original];
copy.push(4);
console.log(original); // [1, 2, 3] (unchanged!)
console.log(copy);     // [1, 2, 3, 4]

// Spread — merge arrays
let front = ["a", "b"];
let back = ["c", "d"];
let all = [...front, "MIDDLE", ...back];
console.log(all); // ["a", "b", "MIDDLE", "c", "d"]

// Destructuring — unpack by position
let [first, second, third] = ["gold", "silver", "bronze"];
console.log(first);  // "gold"
console.log(second); // "silver"

// Skip items with commas
let [, , winner] = [10, 20, 30];
console.log(winner); // 30

// Rest pattern — grab the remaining items
let [head, ...tail] = [1, 2, 3, 4, 5];
console.log(head); // 1
console.log(tail); // [2, 3, 4, 5]

[1, 2, 3]
[1, 2, 3, 4]
["a", "b", "MIDDLE", "c", "d"]
gold
silver
30
1
[2, 3, 4, 5]