- 1: 1, undefined and undefined - 2: ReferenceError: X is not defined - 3: 1, undefined and number - 4: 1, number and number

##### Answer: 3 Of course the return value of foo() is 1 due to the increment operator. But the statement let x = y = 0 declares a local variable x. Whereas y declared as a global variable accidentally. This statement is equivalent to, Since the block scoped variable x is undefined outside of the function, the type will be undefined too. Whereas the global variable y is available outside the function, the value is 0 and type is number.

JavaScript Coding Exercise 2 | JSCodingQuestions.com

javascript

1function foo() {
2
3let x = (y = 0);
4
5x++;
6
7y++;
8
9return x;
10}
11
12console.log(foo(), typeof x, typeof y);

Choose the correct output:

1, undefined and undefined

ReferenceError: X is not defined

1, undefined and number

1, number and number