const numbers = [1, 2, 3, 4, 5];

const result = numbers
  .filter(n => n % 2 === 0)
  .map(n => n * 2)
  .reduce((acc, n) => acc + n, 0);

console.log(result);

const person = {
  name: 'Alice',
  age: 25,
  city: 'Wonderland'
};

const additionalInfo = {
  age: 30,
  occupation: 'Explorer'
};

const combined = {
  ...person,
  ...additionalInfo
};

console.log(combined.age);

function example() {
  console.log(a);
  var a = 10;
  console.log(a);
}
example();

const person = {
  firstName: 'John',
  lastName: 'Doe',
  age: 30,
  getFullName: function() {
    return this.firstName + ' ' + this.lastName;
  }
};

console.log(person.getFullName());

const a = '5';
const b = 5;
const c = 10;

const result1 = a == b;
const result2 = a === b;
const result3 = b < c;
const result4 = b >= c;

console.log(result1, result2, result3, result4);

let a = 5;
let b = a++ + ++a;
console.log(b);

'use strict';

function strictModeExample() {
  undeclaredVariable = 10;
  try {
    console.log(undeclaredVariable);
  } catch (e) {
    console.log('Error:', e.message);
  }
}

strictModeExample();