ternary.js

const getDayOfWeek = dayNumber =>
    dayNumber === 0
        ? "Sunday"
    : dayNumber === 1
        ? "Monday"
    : dayNumber === 2
        ? "Tuesday"
    : dayNumber === 3
        ? "Wednesday"
    : dayNumber === 4
        ? "Thursday"
    : dayNumber === 5
        ? "Friday"
    : dayNumber === 6
        ? "Saturday"
        : "Invalid day number";

console.log( getDayOfWeek( 3 ));
console.log( getDayOfWeek( 10 ));