CodeSignal: Valid Time

validTime.js

/*

Check if the given string is a correct time representation of the 24-hour clock.

Example

For time = "13:58", the output should be
validTime(time) = true;
For time = "25:51", the output should be
validTime(time) = false;
For time = "02:76", the output should be
validTime(time) = false.

*/

function validTime(time) {
    let firstTwo = time.slice(0, 2);
    let lastTwo = time.slice(3, 5);
    
    if(firstTwo < 0 || firstTwo > 23) {
        return false;
    }
    else if(lastTwo < 0 || lastTwo > 59) {
        return false;
    }
    else {
        return true;
    }
}