? ?????? 14?? ?? JavaScript ?? ??? ?????. ? ??? ??? ???? ??? ?? ???? ???????.

1. map(): ? ?? ??? ???? ??? ?? ? ??? ?????. ?? ??? ???? ????.

const numbers = [1, 2, 3];
const doubled = numbers.map(x => x * 2); // [2, 4, 6]
const users = [{ name: 'John' }, { name: 'Jane' }];
const names = users.map(user => user.name); // ['John', 'Jane']

2. filter(): ??? ??? ??? ???? ??? ???? ? ??? ????. ?? ??? ??? ?????.

const nums = [1, 2, 3, 4, 5, 6];
const evenNums = nums.filter(n => n % 2 === 0); // [2, 4, 6]
const products = [{ price: 10 }, { price: 20 }];
const expensive = products.filter(p => p.price > 15); // [{ price: 20 }]

3. reduce(): ?? ??? ??? ?? ???? ?? ??? ????. ??? ????? ???? ???? ?????.

const sum = [1, 2, 3].reduce((acc, curr) => acc + curr, 0); // 6
const cart = [{ price: 10 }, { price: 20 }];
const total = cart.reduce((sum, item) => sum + item.price, 0); // 30

4. forEach(): ? ?? ??? ?? ??? ??? ? ?? ?????. ?? ???? ????(undefined ??).

[1, 2, 3].forEach(n => console.log(n));
['a', 'b'].forEach((item, index) => console.log(`${index}: ${item}`));

5. find(): ??? ??? ??? ???? ? ?? ??? ?????. ??? ???? ??? ??? undefined.
? ?????.

const users2 = [{ id: 1, name: 'John' }, { id: 2, name: 'Jane' }];
const john = users2.find(user => user.name === 'John'); // { id: 1, name: 'John' }
const nums2 = [1, 2, 3, 4];
const firstEven = nums2.find(n => n % 2 === 0); // 2

6. findIndex(): ??? ??? ??? ???? ? ?? ??? ???? ?????. ??? ???? ??? ??? -1? ?????.

const fruits = ['apple', 'banana', 'cherry'];
const bananaIndex = fruits.findIndex(f => f === 'banana'); // 1
const userIndex = users2.findIndex(u => u.id === 2); // 1

7. some(): ??? ?? ?? ??? ??? ??? ??? ??? ???? ????? ??????. ?? ??? ??? ???? true? ????, ??? ??? false? ?????.

const hasEven = [1, 2, 3].some(n => n % 2 === 0); // true
const hasExpensive = products.some(p => p.price > 15); // true

8. every(): ??? ?? ??? ??? ??? ??? ???? ????? ??????. ?? ??? ???? ???? true? ????, ??? ??? false.
? ?????.

const allPositive = [1, 2, 3].every(n => n > 0); // true

9. includes(): ??? ??? ?? ?? ???? ??? ???? true ?? false? ???? ?????.

const numbers2 = [1, 2, 3];
const hasTwo = numbers2.includes(2); // true
const hasZero = numbers2.includes(0); // false

10. indexOf(): ???? ?? ??? ?? ? ?? ? ?? ???? ????? ?? ??? ??? -1? ?????.

const colors = ['red', 'blue', 'green'];
const blueIndex = colors.indexOf('blue'); // 1
const yellowIndex = colors.indexOf('yellow'); // -1

11. slice(): ??? ??? ???? ??? ???? ?? ? ??? ?????.

const arr = [1, 2, 3, 4, 5];
const middle = arr.slice(1, 4); // [2, 3, 4]
const last = arr.slice(-2); // [4, 5]

12. splice(): ?? ??? ?? ?? ????? ? ??? ???? ???? ??? ??? ?????. ?? ??? ?????.

const months = ['Jan', 'March', 'April'];
months.splice(1, 0, 'Feb'); // ['Jan', 'Feb', 'March', 'April']
months.splice(2, 1); // ['Jan', 'Feb', 'April']

13. sort(): ??? ??? ??? ?????. ????? ???? ?????. ????? ???? ????? ?????.

const numbers = [1, 2, 3];
const doubled = numbers.map(x => x * 2); // [2, 4, 6]
const users = [{ name: 'John' }, { name: 'Jane' }];
const names = users.map(user => user.name); // ['John', 'Jane']

14. join(): ??? ?? ??? ?????? ? ???? ???? ?????(??? ??? ???? ??).

const nums = [1, 2, 3, 4, 5, 6];
const evenNums = nums.filter(n => n % 2 === 0); // [2, 4, 6]
const products = [{ price: 10 }, { price: 20 }];
const expensive = products.filter(p => p.price > 15); // [{ price: 20 }]

??? ??? ??? JavaScript ?? ?? ??? ?? ?????.

? ??? ??? ?? ?? JavaScript? ?? ?? ?? ?? ??????!? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!