Why doesn't break work?

Question

Programming

Why doesn't the loop end when I write to the stop prompt, and yes, I'm a beginner:(

let arrA = [];

arrA = fillArr('A');

function fillArr(arrName) {
for (i = 0; ; i++) {
arrA[i] = parseInt(prompt('Elements of arrA'));
if (arrA[i] == 'stop') break;
}
}

Answer 1

I'm not an expert in pros, but according to the text of the error, you need to initialize the u2 variable before using it. Just add for example
u2=0;

Answer 2

You need to use something like this:

Answer 3

And why the hell will there be a stop after the parseInt operation?