How can I select elements with a specific class while excluding those with any additional classes

Suppose, I have three links,

<a class="a b">1</a>
<a class="a">1</a>
<a class="a">1</a>

Now i just want links which only have the class "a". If i use document.querySelectorAll('.a') then i will get all three of the links.

I know i can use document.querySelectorAll('.a:not(.b)'). but for that i need to know all the class name specifically. I just want to get the link which only had the class "a".

>Solution :

I would filter the original results by checking the length of the classList.

const withA = [...document.querySelectorAll("a")];
const onlyA = withA.filter(a => a.classList.length == 1);
console.log(onlyA.length);

<a class="a b">1</a>
<a class="a">1</a>
<a class="a">1</a>