How to save the output of randomization code in Online Experiment

Coding
1

Hello everybody,
I hope you are doing good!
I have five conditions in my experiment and each participant should be assigned to one.
I have written a piece of code to do this and it does its job pretty fine so anyone in a similar situation can use it. The code (JS) is below:

a, b, c, d, e, randnum;
randnum = Math.random();
if (((randnum >= 0) && (randnum < 0.2))) {
    a = 1;
    b = 0;
    c = 0;
    d = 0;
    e = 0;
} else {
    if (((randnum >= 0.2) && (randnum < 0.4))) {
        a = 0;
        b = 1;
        c = 0;
        d = 0;
        e = 0;
    } else {
        if (((randnum >= 0.4) && (randnum < 0.6))) {
            a = 0;
            b = 0;
            c = 1;
            d = 0;
            e = 0;
        } else {
            if (((randnum >= 0.6) && (randnum < 0.8))) {
                a = 0;
                b = 0;
                c = 0;
                d = 1;
                e = 0;
            } else {
                a = 0;
                b = 0;
                c = 0;
                d = 0;
                e = 1;
            }
        }
    }
}

However, in the pilot study, I realized that I have no idea which participant has been assigned to which group. So my question is that how can I save the output of this code component so I know that for example participant 1 has taken task “a” and so on …
Any help is highly appreciated

2 
thisExp.addData(“Group”,”a”)

and equivalent in the other conditions