Advance Array

 // Advance Arrays

//Problem

const array = [1,2,10,16];

const newArray = array.forEach((num) => {

    num * 2;

});

console.log(newArray); // undefined

// how to multiply the number inside this array??

// Sol: 

const array = [1,2,10,16];

const double = [];

const newArray = array.forEach((num) => {

    double.push(num * 2);

});

console.log('forEach: 'double);  // forEach:  (4) [2, 4, 20, 32]

// map, filter, reduce

// map

const mapArray = array.map((num) => {

    return num * 2;

});

console.log('Map: ') // Map: [2, 4, 20, 32] 

// when we have one parameters in map

const array = [1,2,10,16];

const mapArray = array.map(num => num * 2);

console.log('Map: ', mapArray); // Map: [2, 4, 20, 32]

// filter

const array = [1,2,10,16];

const filterArray = array.filter(num => num > 5);

console.log('filter: ', filterArray); // filter: [10, 16]

// reduce 

const array = [1,2,10,16];

const reduceArray = array.reduce((accumulator,num) => {

    return accumulator + num

},0); // if we change 0 to 5 then we get 34 in reduce

console.log('reduce', reduceArray);// reduce 29

//most important topic learn from udemy cource 

// >> Advance Array