Operations Between Numbers

function operationsBetweenNumbers(input) {

    let num1 = Number(input.shift());
    let num2 = Number(input.shift());
    let operation = input.shift();

    let output = "";
    let result = 0;
    switch (operation) {
        case '+':
            result = num1 + num2;
            output = `${num1} + ${num2} = ${result}`;
            break;
        case '-':
            result = num1 - num2;
            output = `${num1} - ${num2} = ${result}`;
            break;
        case '*':
            result = num1 * num2;
            output = `${num1} * ${num2} = ${result}`;
            break;
        case '/':
            if (num2 === 0) {
                output = `Cannot divide ${num1} by zero`;
            } else {
                result = num1 / num2;
                output = `${num1} / ${num2} = ${result.toFixed(2)}`;
            }
            break;
        case '%':
            if (num2 === 0) {
                output = `Cannot divide ${num1} by zero`;
            } else {
                result = num1 % num2;
                output = `${num1} % ${num2} = ${result}`;
            }
            break;
    }

    if (operation === '+' || operation === '-' || operation === '*') {
        if (result % 2 === 0) {
            output = output + " - even";
        } else {
            output = output + " - odd";
        }
    }

    console.log(output);
}

operationsBetweenNumbers(["10", "12", "+"])