when i load this function the value of the array's all the same .. How can i make different array's value everytime i load this function ? btw the num1, num2, opt1, opt2 .. is a random number from
random = () => {
return Math.floor(Math.random() * 15)
}
please help me guys :)this is my code ..
makeQuestion = () => {
questions = [];
for(var i = 0; i < 4; i++){
var obj = {
'question': `Berapakah ${num1} ${operator} ${num2} ?`,
'choice1' : `${opt1}`,
'choice2': `${opt2}`,
'choice3': `${opt3}`,
'choice4': `${final}`,
'answerIndex' : `${2}`,
}
questions.push(obj)
}
}
Related
I have an issue where I have an array containing a deck of cards (['A', 2,3,...'J',...])
I want to be able to pick a number of random cards and then get the total sum of them. for example J,4 should give me the total value of 14.
my current problem is that I can't figure out how to change the strings in the array to a number and
then add those together to get the total sum.
my current code is:
blackjackGame={
'you': 0,
'cards': ['A','2','3','4','5','6','7','8','9','10','J','Q','K'],
'cardsMap' : {'A':1, '2':2, '3':3, '4':4, '5':5, '6':6, '7':7, '8':8, '9':9, '10':10, 'J':10, 'Q':10, 'K':10},
}
let playerCards = 2
let card = [];
const YOU = blackjackGame['you']
// gives me a random card
function randomCard (){
let rand = Math.floor(Math.random()* 13)
return blackjackGame['cards'][rand];
}
// gives me the two starting cards for the player in an array so I can later add more
function start(){
for(let i= 0; i < playerCards; i++){
card.push(randomCard())
}
return card
}
function totalValue (player){
// this is where i have no idea what to do
// let player = card.reduce(function (a,b){
// return a +b
// }, 0)
// return player += blackjackGame['cardsMap'][card[0]]
}
console.log(start())
console.log(showScore(YOU)) ```
PS. I'm trying to create a blackjack game.
Your reduce code is fine. Just add the reference to blackjackGame.cardsMap to retrieve the value that corresponds to card b.
let sum = card.reduce(function(a, b) {
return a + blackjackGame.cardsMap[b];
}, 0);
Note that you cannot return that value via the argument of the function. Instead let the function return it with a return statement:
return sum;
const blackjackGame={
'you': 0,
'cards': ['A','2','3','4','5','6','7','8','9','10','J','Q','K']
}
let playerCards = 2
let card = [];
const YOU = blackjackGame['you']
function getCardValue(card) {
const v = blackjackGame['cards']
if(v.indexOf(card) === -1){
throw Error("not found")
}
// for each card above index 9 (10), always return 10
return v.indexOf(card) > 9 ? 10 : v.indexOf(card) + 1
}
function randomCard (){
let rand = Math.floor(Math.random()* 13)
return blackjackGame['cards'][rand];
}
function deal(){
for(let i= 0; i < playerCards; i++){
card.push(randomCard())
}
return card
}
function calculateValue (cards){
return cards.reduce(function (total, num){
return total + getCardValue(num)
}, 0)
}
document.getElementById('deal').addEventListener('click',(e) => {
const cards = deal()
console.log(cards)
const playerValue = calculateValue(cards)
YOU = playerValue
console.log(playerValue)
})
<html>
<head>
</head>
<body>
<button id="deal">Deal</button>
<span id=cards />
<span id=total />
</body>
</html>
You need a way to map the face to the value. This will work:
function getValueOfCard( face ) {
var cardOrder =" A234567891JQK";
var faceStart = (""+face).substring(0,1);
return Math.min(10, cardOrder.indexOf(faceStart))
}
If you want to get the values of all your cards, simply iterate over them (faster than reduce, and more easy to read).
Your card only needs the face and color, the other values follow.
card = { color: "spades", face : "King" };
getValueOfCard( card.face );
function totalValue ( playerHand ){
// assuming an array of cards is the player hand
var total = 0;
for ( var card in playerHand ) {
total += getValueOfCard( card.face );
}
return total;
}
I also recommend, that you create all your cards in one go, and then shuffle them, by picking two random numbers and switching these two cards. Do this in a loop for a couple of times, and you have a randomized stack of cards, which means you can actually treat it as a stack.
cardColors = ["♠","♥","♦","♣"];
cardFaces = ['A','2','3','4','5','6','7','8','9','10','J','Q','K'];
// create deck of cards
var stackOfCards = [];
for ( var a = 0; a < cardColors.length; a++ ) {
var curColor = cardColors[a];
for ( var i = 0; i < cardFaces.length; i++) {
var curFace = cardFaces[i];
card = { color : curColor, face : curFace };
stackOfCards.push(card);
}
}
// shuffle the deck
// then you can pop cards from the stack to deal...
function start () {
for (let i = 0; i < playerCards; i++) {
cards.push(randomCard())
}
totalValue(cards)
}
function totalValue (cards) {
cards.forEach((card) => {
blackjackGame.you += blackjackGame.cardsMap[card]
})
}
start()
console.log(blackjackGame.you)
You were on the right track with having a map. You can access objects with a variable by using someObj[yourVar]
This is the test code that it's supposed to pass
function makeArray() {
const array = [];
const t = 10;
for (let i = 0; i < t; i++) {
array.push("I am a strange loop.");
}
return [array, t];
}
describe('loops', () => {
jsdom({
src: fs.readFileSync(path.resolve(__dirname, '..', 'loops.js'), 'utf-8'),
});
describe('forLoop(array)', () => {
it('adds `"I am ${i} strange loop${i === 0 ? \'\' : \'s\'}."` to an array 25 times', () => {
const [array, t] = makeArray();
const strangeArray = forLoop(array);
const testArray = strangeArray.slice(array.length);
const first = "I am 1 strange loop.";
const rest = "I am 24 strange loops.";
expect(strangeArray[11]).to.equal(first);
expect(strangeArray[34]).to.equal(rest);
expect(strangeArray.length).to.equal(t + 25);
});
});
});
this is my code to return the function to strangeArray what I am thinking is that 35 is the total number of members in the array and as the test pass requires me to have 'expect(strangeArray[11]).to.equal(first)' 11th value to be equal to my function return as
"I am 1 strange loop."
function forLoop(array) {
for (let i = 0; i < 35; i++) {
if (array[i] === "I am a strange loop.") {
return;
}
else {
array.push("I am ${i} strange loops.");
}
}
return [array,i];
}
Not sure what you mean exactly but I guess you just want the test to pass? The problem is that the first loop has 'loop' as singular and your indexes don't work either since they would start at 11. That's why your code doesn't work. You can just push to the original array.
function forLoop(array){
for(let i = 0; i < 25; i++){
array.push(`I am ${i} strange loop${i > 1 ? '' : 's'}.`)
}
return array
}
I have array with 10 items, I calls one random item using a random number from 1 to 10, what to use to make a random number from 1 to 10, which will not happen again, and when all 10 is used, the program stops randomly? code
const num = () => Math.floor(Math.random() * 10);
const postWord = () => {
randomWord = word.innerText = words[num()].PL;
}
postWord();
submit.addEventListener("click", function() {
postWord();
});
Have you ever considered to move the array items?
var range = 10; // global variable
const num = () => Math.floor(Math.random() * range);
const postWord = () => {
randomWord = word.innerText = words[num()].PL;
for (var i=num(); i < range; i++) {
var temp = words[i];
words[i] = words[i+1];
words[i+1] = temp;
}
range--;
}
postWord();
submit.addEventListener("click", function() {
if (range) {
postWord();
}
});
I am not that familiar with JS but I guess my code can at least demonstrate my point.
Can anyone help me to do this? The function is empty below and I am unsure how to proceed. I have the factorized number showing on the webpage now I would like the math to show before it. Something like this;
A user inputs: 3
Our site outputs: "1 x 2 x 3 = 6"
function factorialize(num) {
var total = 1;
if (num > 1) {
for (var i = 1; i <= num; i += 1) {
total *= i;
}
}
return total;
}
function showMath() {
};
$(document).ready(function() {
$("form#new-item").submit(function(event) {
event.preventDefault();
var userInput = parseInt($("input#input1").val());
var result = factorialize(userInput);
var myWork = showMath(userInput);
// var
$("#output").text(myWork + " = " + result);
});
});
You should build up an array of all the factors. Then it is easy to reduce() the array to a single value or join() it into a string.
function toFactorialArray(num){
var n = num,
arr = [n];
while (--n) arr.push(n);
return arr;
}
function getResult(arr){
return arr.reduce(
function( memo, current ) {
return memo * current
}, 1
);
}
function getWork(arr){
return arr.reverse().join(' * ');
}
$(document).ready(function() {
$("form#new-item").submit(function(event) {
event.preventDefault();
var userInput = parseInt($("input#input1").val());
var factors = toFactorialArray(userInput);
var result = getResult(factors);
var myWork = getWork(factors);
$("#output").text(myWork + " = " + result);
});
});
I've a problem that has been bugging me for a while now.
I have 14 divs each which must be assigned a random ID (between 1 and 14) each time the page loads.
Each of these divs have the class ".image-box" and the format of the ID I'm trying to assign is 'box14'
I have the JS code working to assign random IDs but I'm having trouble not getting the same ID to assign twice.
JavaScript
var used_id = new Array();
$( document ).ready(function() {
assign_id();
function assign_id()
{
$('.image-box').each(function (i, obj) {
random_number();
function random_number(){
number = 2 + Math.floor(Math.random() * 14);
var box_id = 'box' + number;
if((box_id.indexOf(used_id) !== -1) === -1)
{
$(this).attr('id',box_id);
used_id.push(box_id);
}
else
{
random_number();
}
}
});
}
});
Thanks for your help,
Cheers
Mmm, random...
Instead of using a randomly generated number (which, as your experiencing, may randomly repeat values) just use an incrementally-updated counter when assigning IDs.
function assign_id() {
var counter = 0;
$('.image-box').each(function (i, obj) {
$(this).attr('id','image-box-' + counter++); }
});
}
I think this is what you want and DEMO
$(document).ready(function() {
assign_id();
});
function assign_id() {
var numberOfDiv = $('.image-box').length;
var listOfRandomNumber = myFunction(numberOfDiv);
$('.image-box').each(function(i, obj) {
$(this).attr("id",listOfRandomNumber[i]);
});
};
//Getting List Of Number contains 1 to the number of Div which is
//14 in this case.
function myFunction(numberOfDiv ) {
for (var i = 1, ar = []; i < numberOfDiv +1 ; i++) {
ar[i] = i;
}
ar.sort(function() {
return Math.random() - 0.5;
});
return ar;
};
I would suggest to have a global array like u have for user_id and push assigned div ids into array. Then you can check before assigning random id to div. If it is assigned use different one.
Hope this helps.
Cheers.
First how you'd use my implementation:
var takeOne = makeDiminishingChoice(14);
In this case, takeOne is a function that you can call up to 14 times to get a unique random number between 1 and 14.
For example, this will output the numbers between 1 and 14 in random order:
for (var i = 0; i < 14; i++) {
console.log(takeOne());
}
And here is the implementation of makeDiminishingChoice itself:
var makeDiminishingChoice = function (howMany) {
// Generate the available choice "space" that we can select a random value from.
var pickFrom = [];
for (var i = 0; i < howMany; i++) {
pickFrom.push(i);
}
// Return a function that, when called, will return a value from the search space,
// until there are no more values left.
return function() {
if (pickFrom.length === 0) {
throw "You have requested too many values. " + howMany + " values have already been used."
}
var randomIndex = Math.floor(Math.random() * pickFrom.length);
return pickFrom.splice(randomIndex, 1)[0];
};
};
It's better to use incremental values(or something like (new Date).getTime()) if all you want to do is assign unique values. But if, for some reason, you must have randomly-picked values(only from 1-14) then use something like this to pick unique/random values
var arrayId = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14];
function getRandomId(array) {
var randomIndex = Math.floor(Math.random() * (array.length));
var randomId = array.splice(randomIndex, 1);
return randomId[0];
}
Now getRandomId(arrayId) would return a randomly picked value from your array and then remove that value so that it is not repeated.