Comparing two arrays and common objects add to new array

Question

I got this code:

var counter = 0,
randoms = [],
randoms1 = [],
n;

for (n = 0; n < 5; n++) {
randoms.push(Math.floor(Math.random() * 49 + 1));
randoms1.push(Math.floor(Math.random() * 49 + 1));
}

With these 2 arrays how can I check if there is a common number in them, and this number add it to a new array?

First simple approach that comes to mind: For each element in `randoms`, iterate over `randoms1` and compare the values. — Felix Kling, Sep 24 '14 at 15:42
duplicate of http://stackoverflow.com/questions/1885557/simplest-code-for-array-intersection-in-javascript/1885569#1885569 — Rhumborl, Sep 24 '14 at 15:43
@Rhumborl im not talented in searching, not even close to searching a topic named like that lol — Alpha2k, Sep 24 '14 at 15:45

score 2 · Accepted Answer · answered Sep 24 '14 at 15:42

2

Loop over one of the arrays and check:

var matches = [];
for (var i = 0; i < randoms.length; i++) {
    if (randoms1.indexOf(randoms[i]) > -1) matches.push(randoms[i]);
}

answered Sep 24 '14 at 15:42

tymeJV

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score 0 · Answer 2 · answered Sep 24 '14 at 15:48

--> Simple and heavy checking : Double for loop .
--> Harder but smarter and a bit lighter : use (indexOf(smthg) > -1)

--> My favorite :

randoms = [];

//Populating
for (var n = 0; n < 5; n++) {
randoms[Math.floor(Math.random() * 49 + 1)] = (Math.floor(Math.random() * 49 + 1));
}

//Checking
for (var n in randoms) {
if (randoms[randoms[n]]) console.log("Found One !");
}

Comparing two arrays and common objects add to new array

2 Answers2