A basic time difference calculator in google script js

function dodiff(a, b) {
    if (a)
        a = fix(a);
    if (b)
        b = fix(b);
    if (Array.isArray(a) && Array.isArray(b)) {
        if (b[1] > a[1]) m = b[1] - a[1];
        else {
            m = b[1] - a[1] + 60;
            b[0]--;
        }
        if (b[0] >= a[0]) h = b[0] - a[0];
        else {
            h = b[0] - a[0] + 12;
        }
        m = m / 60;
        return (h + m).toPrecision(4);
    }
}

function fix(a) {
    if (a)
        x = a.toString().replace(" ", '').replace("am", "").replace("pm", "").replace("PM", "").replace("AM", "");
    x = x.split(":");
    x[0] = parseInt(x[0]);
    x[1] = parseInt(x[1]);
    return x;
}