What will this code output to the console and why?
Difficulty: Hard😤

function addToArray(arr, value) {
  arr.push(value);
  return arr;
}

const numbers = [1, 2, 3];
const result = addToArray(numbers, 4);
console.log(result);
console.log(numbers);

What will this code output to the console and why?
Difficulty: Average🤨

function createAccumulator(initialValue) {
  let total = initialValue;

  return function(amount) {
    total += amount;
    return total;
  };
}

const accumulator = createAccumulator(10);

console.log(accumulator(5));  
console.log(accumulator(10)); 
console.log(accumulator(-5)); 

const anotherAccumulator = createAccumulator(100);
console.log(anotherAccumulator(50));

JavaScript Task
Write a function findMax(arr) that takes an array of numbers and returns the largest number in the array.
Difficulty: Easy😁

function findMax(arr) {

}

console.log(findMax([3, 5, 7, 2, 8]));

Find the error in the code.
Difficulty: Average🤨

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

function sumArray(arr) {
    return arr.reduce((accumulator, current) => {
        return accumulator + current;
    }, 0);
}

console.log('Sum:', sumArray(numbers));

numbers = '1, 2, 3, 4, 5'; 
console.log('Sum:', sumArray(numbers));

JavaScript Task
Write a function isEven that takes a number as an argument and returns true if the number is even and false if it is odd.
Difficulty: Easy😁

function isEven(num) {
    
}

console.log(isEven(4));  
console.log(isEven(7)); 
console.log(isEven(0));  
console.log(isEven(-2));

Find the error in the code.
Difficulty: Average🤨

function processData(data) {
    let result = data.map(item => item.value);
    return result;
}

let inputData = null;

console.log(processData(inputData));

JavaScript Task
Remove all empty strings from the array.
Difficulty: Average🤨

let arr = [1, '', 2, 3, '', 5];

Find the error in the code.
Difficulty: Hard😤

function processArray(arr) {
    let result = [];
    
    arr.forEach(item => {
        if (item != '') { 
            result.push(item);
        } else if (typeof item === 'number') { 
            result.push(item * 2);
        }
    });

    return result;
}

let data = [1, '', 2, 3, '', 5, null, undefined, 'hello'];

console.log(processArray(data));