JS Interview #17: Sum of two empty arrays in JavaScript

Is the sum of two arrays equal to false?

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To analyze this code snippet we need to understand how type conversion works in JS.

When we try to sum two arrays using the + operator, the arrays are first converted to strings and then these strings are concatenated.

An empty array [] is evaluated as an empty string. The sum of two empty strings is still an empty string.

Now, is an empty string equal to false or not?

The comparison here is done using the == operator. This operator is used to check loose equality and does implicit type conversion.

In this case, empty string and false are considered equal and the condition of the if statement will be evaluated to true.

If you want to use a strict comparison which respects the types of values you compare, you should use the strict equality operator ===.

Here, you can find more information on basic math operations is JavaScript.

ANSWER: the string same will be logged to the console.