Get the intersection of two sorted arrays of numbers or strings.

intersect.js

// Returns the intersection of two sorted arrays of numbers or strings.
function intersectArrays(a, b) {
    var array = [], ai = 0, alen = a.length, bi = 0, blen = b.length;

    while (ai < alen && bi < blen) {
        if (a[ai] < b[bi]) {
            ai++;
        } else if (a[ai] > b[bi]) {
            bi++;
        } else {
            array.push(a[ai]);
            ai++;
            bi++;
        }
    }

    return array;
}