function executeOperationsOnNumbers(op)
{
    var num;
    // - Begin switch
    switch(op)
    {
        // - Begin first case
        case "checkPrime":
            var sum;
            while (true)
            {
                var data = window.prompt("Enter a positive number:");
                var number = parseInt(data, 10);
                sum = checkPrimeNumber(number);
                // - This break exits the while loop
                if (sum == true)
                {break};
            }
            var num = + number + " is a prime number"
            window.alert(num);
            output.innerHTML = num;
            console.log(num);
            // - This break ends the case
            break;
        case "findPrime":
            var sum;
            while (true)
            {
                var data = window.prompt("Enter a positive number:");
                var number = parseInt(data, 10);
                sum = findPrimeNumbers(number);
                // - This break exits the while loop
                if(number > 0)
                {break};
            }
            var num = "There are " + sum.length
            + " prime numbers <= " + number + "\n"
            + "Prime Numbers <= " + number + ": " + sum

            window.alert(num);
            output.innerHTML = num;
            console.log(num);
            // - This break ends the case
            break;
        case "calcSum":

            var sum;
            while (true)
            {
                var data = window.prompt("Enter a positive integer:");
                var number = parseInt(data, 10);
                sum = calculateSum(number);
                if (Number.isInteger(sum) && sum> 0)
                // - This break exits the while loop
                {break};
            }
            var num2 = "The sum of the integers from 1 to "
                + number + " is " + sum;
            window.alert(num2);
            output.innerHTML = num2;
            console.log(num2);
            // - This break ends the case
            break;
        // - Begin default
        default:
            console.log('default');
            // - This break ends the default
            break;
    }
    // - End switch
}