return the first non repeating character in a string in javascript

Question

So I tried looking for this in the search but the closest I could come is a similar answer in several different languages, I would like to use Javascript to do it.

T

Answer 1

Here is my solution which have time complexity of o(n)

function getfirstNonRepeatingCharacterInAString(params) {
    let count = {};
    for (let i = 0; i < params.length; i++) {
        let count1 = 0;
        if (!count[params.charAt(i)]) {
            count[params.charAt(i)] = count1 + 1;
        }
        else {
            count[params.charAt(i)] = count[params.charAt(i)] + 1;
        }
    }
    for (let key in count) {
        if (count[key] === 1) {
            return key;
        }
    }
    return null;
}
console.log(getfirstNonRepeatingCharacterInAString("GeeksfoGeeks"));