coffeeLover.js

function coffeeLover(input) {
    let index = 0;
    let coffeeList = input[index].split(` `);
    index++;
    let cmdCounter = Number(input[index]);
    index++;

    for (let i = 0; i < cmdCounter; i++) {
        let cmdList = input[index].split(` `);
        index++;
        let cmd = cmdList[0];
        let value = cmdList[1];

        switch(cmd) {
            case "Include":
                coffeeList.push(value);
                break;
            case "Remove":
                if (value === "first") {
                    coffeeList.splice(0, Number(cmdList[2]));
                } else if (value === "last") {
                    coffeeList.splice(-1, Number(cmdList[2]));
                }
                break;
            case "Prefer":
                if (coffeeList[Number(value)] !== undefined && coffeeList[Number(cmdList[2])] !== undefined) {
                    let index = Number(value);
                    let index2 = Number(cmdList[2]);
                    let indexBackup = coffeeList[index2];
                    coffeeList[index2] = coffeeList[index];
                    coffeeList[index] = indexBackup;
                }
                break;
            case "Reverse":
                coffeeList = coffeeList.reverse();
                break;
        }
    }
    console.log("Coffees:");
    console.log(coffeeList.join(` `));
}