Find second largest In an array

findSecondLargestInArray.js

function findSecondLargest(arr) {
    let max = arr[0];
    let secondMax = arr[0];
    arr.forEach((elem) => {
        if(elem > max) {
            secondMax = max;
            max = elem;
        } else if(elem<max && elem>secondMax) {
            secondMax = elem;
        }
    });
    return secondMax;
}

const arr = [2,17,4,7,9,42,33,3,7];
findSecondLargest(arr);