prompt() in JS gives you string, how to have number?

Question

When I use prompt() in JavaScript, I receive a string variable. What do I do so that prompt() gives a number variable, or is there another way besides prompt() ?

Answer 1

For example,
var a=prompt();
alert(parseInt(a)+1);

Answer 2

tq

Answer 3

Be careful, in some situations it returns null.

Answer 4

@Petr Show me how to use it pls

Answer 5

Its not work...
https://code.sololearn.com/W22Oei0bWsS7/?ref=app

Answer 6

parseInt(string) is integer in JavaScript.