What will be the output of the following JavaScript code?
var quiz=[1,2,3];
var js=[6,7,8];
var result=quiz.concat(js);
document.writeln(result);
a)
1, 2, 3, 6, 7, 8
b)
123
c)
1, 2, 3
d)
Error
Correct answer is option 'A'. Can you explain this answer?

Question

What will be the output of the following JavaScript code?

var quiz=[1,2,3];
var js=[6,7,8];
var result=quiz.concat(js);
document.writeln(result);

a)
1, 2, 3, 6, 7, 8
b)
123
c)
1, 2, 3
d)
Error

Correct answer is option 'A'. Can you explain this answer?

Answer

Concatenating Arrays in JavaScript

In JavaScript, the concat() method is used to join two or more arrays into a new array.

Syntax:
array1.concat(array2, array3, ..., arrayX)

Explanation

In the given code, there are two arrays: quiz and js. The concat() method is used to combine these two arrays into a new array called result.

The resulting array will have all the elements of the first array (quiz), followed by all the elements of the second array (js).

The document.writeln() method is used to display the contents of the resulting array.

Output
When the code is executed, the output will be:
1, 2, 3, 6, 7, 8

So, the correct answer is option 'A'.

Answer

Concat is a predefined function in the array library in Javascript. The concat function is used to combine the value of two arrays.
i.e.1, 2, 3, 6, 7, 8

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