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Trying to find the index values of an array which consist of objects

why is it that i am unable to find the index values of the 'deck' array using deck[0] but this notation works for suits[0]
I am trying to find the index values of my 'deck' array but i am unsure why i keep getting 'undefined'.
var deck = [];
var suits = ["diamonds","hearts","clubs","spades"];
var value = ["A", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K"];
function genDeck()
{
for(var i = 0; i < suits.length; i++)
{
for(var x = 0; x < value.length; x++){
var card = {Value:value[x], Suit:suits[i]};
deck.push(card);
}
}
return deck;
}
window.onload = function () {
genDeck();
};
var randomNum = Math.floor(Math.random() * 52);

You aren't adding anything to the deck array. You need to call
deck.push(card)
EDIT: Here's the working example code:
var deck = [];
var suits = ["diamonds","hearts","clubs","spades"];
var value = ["A", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K"];
function genDeck()
{
for(var i = 0; i < suits.length; i++)
{
for(var x = 0; x < value.length; x++){
var card = {Value:value[x], Suit:suits[i]};
deck.push(card);
}
}
return deck;
}
window.onload = function () {
genDeck();
console.log('First Item: ', deck[0])
};
var randomNum = Math.floor(Math.random() * 52);
Note that you have to call console.log after you've called genDeck in your window.onload function.

Concat multiple arrays into one array without duplicates [duplicate]

This question already has answers here:
Get all unique values in a JavaScript array (remove duplicates)
(91 answers)
Closed 6 years ago.
I want to push values of 3 arrays in a new array without repeating the same values
var a = ["1", "2", "3"];
var b = ["3", "4", "5"];
var c = ["4", "5", "6"];
var d = [];
function newArray(x, y, z) {
for(var i = 0; i < d.length; i++) {
if(d.length == -1) {
d[i].push(a[i])
}
}
for(var i = 0; i < d.length; i++) {
if(d.length == -1) {
d[i].push(y[i])
}
}
for(var i = 0; i < d.length; i++) {
if(d.length == -1) {
d[i].push(z[i])
}
}
}
newArray(a, b, c);
d = ["1", "2", "3", "4", "5", "6"];

You can use concat() and Set together as below,
var a = ["1","2","3"];
var b = ["3","4","5"];
var c = ["4","5","6"];
var d = a.concat(b).concat(c);
var set = new Set(d);
d = Array.from(set);
console.log(d);

If your goal is to remove duplicates, you can use a set,
var arr = [1, 2, 3, 4, 5, 5, 6, 6, 6, 7]
var mySet = new Set(arr)
var filteredArray = Array.from(mySet)
console.log(filteredArray.sort()) // [1,2,3,4,5,6,7]

var a = ["1","2","3"]
, b = ["3","4","5"]
, c = ["4","5","6"]
, d = [];
function newArray(x,y,z) {
x.concat(y,z).forEach(item =>{
if (d.indexOf(item) == -1)
d.push(item);
});
return d;
}
console.log(newArray(a,b,c));

You could save yourself some time and effort with the very useful utility library Lodash.
The function you're looking for is Union
As stated by Lodash:
Creates an array of unique values, in order, from all given arrays
using SameValueZero for equality comparisons.
Example
_.union([2], [1, 2]);
// => [2, 1]

var a = ["1", "2", "3"];
var b = ["3", "4", "5"];
var c = ["4", "5", "6"];
var d = [];
var hash = [];
AddToHash(a);
AddToHash(b);
AddToHash(c);
function AddToHash(arr) {
for (var i = 0; i < arr.length; i++) {
if (!hash[arr[i]]) {
hash[arr[i]] = 1;
} else
hash[arr[i]] += 1;
}
}
for (var i = 0; i < hash.length; i++) {
d.push(i);
}
console.log(d);
Hope this helps

Here is another version:
var d = b.concat(c);
d.forEach(function(el) {
if (a.indexOf(el) === -1) {
a.push(el)
}
})
ES6 version:
let d = b.concat(c);
d.forEach(el => {
if (a.indexOf(el) === -1) {
a.push(el)
}
})

loop minute in javascript

I have code like this:
var hour = 7;
for (var i = 0;i <= 1; i++ ){
var minute = 0;
console.log((i + hour) % 24);
}
when I run it, I get result like this:
7
8
my question: how to add the value in format minute ex: 0-59
so I wanna loop the data like this:
7:0
7:1
7:2
s.d
7:59
8:0

You could use a new array to store all your unique values. You will need to look into the new "uniques" array, if the value alreay exists and then use the default value:
var number= ["1", "2", "3", "4", "5", "6", "6"];
var default = 0;
var uniques = [];
var result = [];
for(var i=0; i < number.length; i++) {
if(!inArray(number[i], uniques) {
uniques.push(number[i]);
result.push(number[i]);
console.log(number[i]);
} else {
console.log(default);
result.push(default);
}
}
function inArray(needle, haystack) {
var length = haystack.length;
for(var i = 0; i < length; i++) {
if(haystack[i] == needle) return true;
}
return false;
}

You could use Array#indexOf and check against the actual index. If you get the same index, then show the element, otherwise use a default value instead.
var number= ["1", "2", "3", "4", "5", "6", "6"];
for (var i = 0; i < number.length;i++) {
console.log(number.indexOf(number[i]) === i ? number[i] : undefined);
}

Use map to get the new array, and in the callback store each item in a set to know if it's a duplicate or not.
var number = ["1", "2", "3", "4", "5", "6", "6"];
var s = new Set();
console.log(number.map(n => s.has(n) ? undefined : s.add(n) && n));
If the non-equality of your values is respected by stringification, you can use a plain object, without needing ES6 features:
var number = ["1", "2", "3", "4", "5", "6", "6"];
var s = Object.create(null);
console.log(number.map(function(n) {
if (n in s) return undefined;
s[n] = true;
return n;
}));

Invalid left-hand side expression

I'm trying to figure out why the bottom function I've written isn't working properly. Whenever I try to test it out, I get the following error: Uncaught ReferenceError: Invalid left-hand side expression in postfix operation. I'm assuming it's because the code is failing to recognize the "x" string as being the same as the variable x once it's been stripped of it quotation marks when adding to the value of x. Can someone help me finesse this in a way to make it work? If not, can you suggest some alternate approach? Thanks in advance!
var grid = [[null, null, null],
[null, null, null],
[null, null, null]];
function checkWin() {
vals = ["x", "o"];
var x = 0;
var o = 0;
for (var k = 0; k < vals.length; k++) {
var value = vals[k];
for (var i = 0; i < 3; i++) {
if (grid[i][i] === value) {
(value.replace(/['"]+/g, '')) ++;
}
if (grid[2 - i][i] === value) {
(value.replace(/['"]+/g, '')) ++;
}
for (var j = 0; j < 3; j++) {
if (grid[i][j] === value) {
(value.replace(/['"]+/g, '')) ++;
}
if (grid[j][i] === value) {
(value.replace(/['"]+/g, '')) ++;
}
}
}
}
if (x === 3) {
alert("X wins!");
} else if (o === 3) {
alert("O wins!");
}
}

The following uses objects. The different grid definitions were tested
var grid = [
["o", "x", "x"],
["o", "x", "x"],
["o", "", "o"]];
var grid = [
["o", "x", ""],
["x", "x", "x"],
["o", "o", ""]];
var grid = [
["x", "x", ""],
["o", "x", "o"],
["o", "o", "x"]];
var grid = [
["x", "x", "o"],
["x", "o", "x"],
["o", "x", "x"]];
checkWin(grid)
function checkWin(grid) {
var vals = [{player: "x", value: 0}, {player: "o", value: 0}];
for (var k = 0; k < vals.length; k++) {
for (var i = 0; i < 3; i++) {
// check win by row
vals[k].value = 0;
// check win by col
for (var j = 0; j < 3; j++) {
if (grid[i][j] === vals[k].player) {
vals[k].value++;
}
}
if (vals[k].value === 3) {
alert(vals[k].player + " wins by row " + (i+1));
return vals[k].player;
}
// check win by col
vals[k].value = 0;
for (var j = 0; j < 3; j++) {
// check col
if (grid[j][i] === vals[k].player) {
vals[k].value++;
if (vals[k].value === 3) {
// break if you want to know what column won by
break;
}
}
}
if (vals[k].value === 3) {
alert(vals[k].player + " wins by col " + (i+1));
return vals[k].player;
}
}
}
// check win by diag l to r
for (var k = 0; k < vals.length; k++) {
vals[k].value = 0;
for (var i = 0; i < 3; i++) {
if (grid[i][i] === vals[k].player) {
vals[k].value++;
}
}
if (vals[k].value === 3) {
alert(vals[k].player + " wins by diag left to right!");
return vals[k].player;
}
}
// check win by diag r to l
for (var k = 0; k < vals.length; k++) {
vals[k].value = 0;
for (var i = 0; i < 3; i++) {
if (grid[i][2-i] === vals[k].player) {
vals[k].value++;
}
}
if (vals[k].value === 3) {
alert(vals[k].player + " wins by diag right to left!");
return vals[k].player;
}
}
}

What about put your data in a object like this:
var _ = {
x : 0,
o : 0
};
and change the value like this:
_[value]++;
I hope this helps.

how can i compare two arrays in Javascript by using binarysearch?

How can i use a binary search to compare two arrays and count the number of times it matched, i did find some here where one item was compared to an array..follwing is regular one for example ..thanx for the help.
var a = ["1", "2", "3", "4", "5", "6", "7"];
var b = ["8", "1", "3", "9", "4", "6", "8"];
var count = 0;
for (i = 0; i < a.length; i++) {
for (j = 0; j < b.length; j++) {
if (a[i] == b[j]) count += 1;
}
}
document.write(count);
I tried to do this ..
for (i = 0; i < a.length; i++) {
var left = 0;
var right = b.length - 1;
while (left <= right) {
var mid = parseInt((left + right) / 2);
if (b[mid] == a[i]) {
count += 1;
} else if (b[mid] < a[i]) {
left = mid + 1;
}
else {
right = mid - 1;
}
}
}
document.write(count);

Linearly go through the b array and use a binary search of the a array.
function binarySearch(a, value) {
var left = 0;
var right = a.length - 1;
while (left <= right) {
var mid = (left + right) >> 1;
if (a[mid] === value) {
return mid;
} else if (a[mid] < value) {
left = mid + 1;
}
else {
right = mid - 1;
}
}
return -1;
}
var a = ["1", "2", "3", "4", "5", "6", "7"];
var b = ["8", "1", "3", "9", "4", "6", "8"];
var count = 0;
b.forEach(function(value) { if (binarySearch(a, value) >= 0) ++count; });