function shop(arg1, arg2, arg3) {

    let day = arg2;
    let fruit = arg1;
    let quant = Number(arg3);
    let price = 0;
    let error = false;

    if (day === "Monday" || day === "Tuesday" || day === "Wednesday" || day === "Thursday" || day === "Friday") {

        switch (fruit) {

            case "banana": price = quant * 2.5; break;
            case "apple": price = quant * 1.2; break;
            case "orange": price = quant * 0.85; break;
            case "grapefruit": price = quant * 1.45; break;
            case "kiwi": price = quant * 2.7; break;
            case "pineapple": price = quant * 5.5; break;
            case "grapes": price = quant * 3.85; break;
            default: error = true; console.log("error"); break;


        }
        if (!error) {
            console.log(price.toFixed(2))
        }
    } else if (day === "Saturday" || day === "Sunday") {

        switch (fruit) {

            case "banana": price = quant * 2.7; break;
            case "apple": price = quant * 1.25; break;
            case "orange": price = quant * 0.9; break;
            case "grapefruit": price = quant * 1.6; break;
            case "kiwi": price = quant * 3; break;
            case "pineapple": price = quant * 5.6; break;
            case "grapes": price = quant * 4.2; break;
            default: error = true; console.log("error"); break;

        }
        if (!error) {
            console.log(price.toFixed(2));
        }
    } else {
        console.log("error")
    }
}