Coffee Machine

function coffeeMachine(input) {
    let coffee = input[0];
    let sugar = input[1];
    let count = Number(input[2]);
    let sum = count;

    if (coffee === "Espresso") {
        if (sugar === "Without") {
            sum *= 0.9 * 0.65;
        } else if (sugar === "Extra") {
            sum *= 1.2;
        }
        if (count > 5) {
            sum *= 0.75;
        }
    } else if (coffee === "Cappuccino") {
        if (sugar === "Without") {
            sum *= 0.65;
        } else if (sugar === "Normal") {
            sum *= 1.2;
        } else {
            sum *= 1.6;
        }
    } else {
        if (sugar === "Without") {
            sum *= 0.5 * 0.65;
        } else if (sugar === "Normal") {
            sum *= 0.6;
        } else {
            sum *= 0.7;
        }
    }
    if (sum > 15) {
        sum *= 0.8;
    }
    console.log(`You bought ${count} cups of ${coffee} for ${sum.toFixed(2)} lv.`);
}

РЕШЕНИЕ СЪС SWITCH И ТЕРНАРЕН ОПЕРАТОР:

function coffeeMachine(input) {
    let coffee = input[0];
    let sugar = input[1];
    let count = Number(input[2]);
    let sum = count;

    switch (coffee) {
        case "Espresso":
            sum *= (sugar === "Without" ? 0.9 * 0.65 : sugar === "Extra" ? 1.2 : 1) * (count > 5 ? 0.75 : 1);
            break;

        case "Cappuccino":
            sum *= sugar === "Without" ? 0.65 : sugar === "Extra" ? 1.6 : 1.2;
            break;

        case "Tea":
            sum *= sugar === "Without" ? 0.5 * 0.65 : sugar === "Extra" ? 0.7 : 0.6;
            break;
    }
    console.log(`You bought ${count} cups of ${coffee} for ${(sum * (sum > 15 ? 0.8 : 1)).toFixed(2)} lv.`);
}

РЕШЕНИЕ САМО С ТЕРНАРЕН ОПЕРАТОР:

function coffeeMachine(input) {
    let coffee = input[0];
    let sugar = input[1];
    let count = Number(input[2]);

    let sum = (coffee === "Espresso" ? ((sugar === "Without" ? 0.9 * 0.65 : sugar === "Extra" ? 1.2 : 1) * (count > 5 ? 0.75 : 1)) :
               coffee === "Cappuccino" ? (sugar === "Without" ? 0.65 : sugar === "Extra" ? 1.6 : 1.2) :
               (sugar === "Without" ? 0.5 * 0.65 : sugar === "Extra" ? 0.7 : 0.6)) * count;

    console.log(`You bought ${count} cups of ${coffee} for ${(sum * (sum > 15 ? 0.8 : 1)).toFixed(2)} lv.`);
}