Find best couples

main.js

let request = require('request');

const MORE_OR_LESS = 1;
const NB_DAYS = 2;

function addIfNotExist(participantsAvailable, participants, iDate) {
    for (let i = 0; i < participants.length; i++) {

        if (participants[i].preferences[iDate] > 0
            && participantsAvailable.indexOf(participants[i]) === -1
        ) {
            participantsAvailable.push(participants[i]);
        }
    }
}

function findResults(options, participants, dateTab) {
    const participantsAvailable = [];
    let i;

    for (i = 0; i < dateTab.length; i++) addIfNotExist(participantsAvailable, participants, dateTab[i]);

    if (participantsAvailable.length >= participants.length - MORE_OR_LESS) {
        let msg = "Le ";

        for (i = 0; i < dateTab.length - 2; i++) msg += options[dateTab[i]].text + ", ";
        msg += options[dateTab[i++]].text + " et ";
        msg += options[dateTab[i]].text + ", sont les jours optimaux (avec %d de marge et sur %d jours)";

        console.log(msg, MORE_OR_LESS, NB_DAYS);
    }
}

function searchForAll(options, participants, iDates, remainingDays) {
    if (remainingDays === 0) return findResults(options, participants, iDates);

    let arrayToSend;
    for (let i = 0; i < options.length; i++) {
        arrayToSend = [...iDates];
        arrayToSend.push(i);
        searchForAll(options, participants, arrayToSend, remainingDays - 1);
    }
}


request('https://beta.doodle.com/api/v2.0/polls/m9r29w79i4is42zi', (error, response, body) => {
    let data = JSON.parse(body);


    let options = data.options;
    let participants = data.participants;

    searchForAll(options, participants, [], NB_DAYS);
});