08. On Time for the Exam

function onTimeForTheExam(input) {
    let hourExam = parseInt(input[0]);
    let minuteExam = parseInt(input[1]);
    let hoursStudent = parseInt(input[2]);
    let minuteStudent = parseInt(input[3]);

    let examMinutes = hourExam * 60 + minuteExam;
    let studentMinutes = hoursStudent * 60 + minuteStudent;
    let time = Math.abs(studentMinutes - examMinutes);

    if (studentMinutes > examMinutes) {
        console.log("Late");
        if (time < 60) {
            console.log(`${time} minutes after the start`);
        } else if (time % 60 < 10) {
            console.log(`${parseInt(time / 60)}:0${time % 60} hours after the start`);
        } else {
            console.log(`${parseInt(time / 60)}:${time % 60} hours after the start`);
        }
    } else {
        if (time <= 30) {
            console.log("On time");
        } else {
            console.log("Early");
        }
        if (time !== 0) {
            if (time < 60) {
                console.log(`${time} minutes before the start`);
            } else if (time >= 60 && time % 60 < 10) {
                console.log(`${parseInt(time / 60)}:0${time % 60} hours before the start`);
            } else if (time !== 0) {
                console.log(`${parseInt(time / 60)}:${time % 60} hours before the start`);
            }
        }
    }
}

РЕШЕНИЕ СЪС String() И PadStart():

function onTimeForTheExam(input) {
    let hourExam = parseInt(input[0]);
    let minuteExam = parseInt(input[1]);
    let hoursStudent = parseInt(input[2]);
    let minuteStudent = parseInt(input[3]);

    let examMinutes = hourExam * 60 + minuteExam;
    let studentMinutes = hoursStudent * 60 + minuteStudent;
    let time = Math.abs(studentMinutes - examMinutes);

    if (studentMinutes > examMinutes) {
        console.log("Late");
        if (time < 60) {
            console.log(`${time} minutes after the start`);
        } else {
            console.log(`${parseInt(time / 60)}:${String(time % 60).padStart(2, '0')} hours after the start`);
        }
    } else {
        if (time <= 30) {
            console.log("On time");
        } else {
            console.log("Early");
        }
        if (time !== 0) {
            if (time < 60) {
                console.log(`${time} minutes before the start`);
            } else {
                console.log(`${parseInt(time / 60)}:${String(time % 60).padStart(2, '0')} hours before the start`);
            }
        }
    }
}

РЕШЕНИЕ С ТЕРНАРЕН ОПЕРАТОР:

function onTimeForTheExam(input) {
    let hourExam = parseInt(input[0]);
    let minuteExam = parseInt(input[1]);
    let hoursStudent = parseInt(input[2]);
    let minuteStudent = parseInt(input[3]);

    let examMinutes = hourExam * 60 + minuteExam;
    let studentMinutes = hoursStudent * 60 + minuteStudent;
    let time = Math.abs(studentMinutes - examMinutes);

    console.log(studentMinutes > examMinutes ? "Late" : time <= 30 ? "On time" : "Early");
    console.log(time !== 0 ? (time < 60 ? `${time} minutes ${studentMinutes > examMinutes ? 'after' : 'before'} the start` :
        `${parseInt(time / 60)}:${time % 60 < 10 ? '0' : ''}${time % 60} hours ${studentMinutes > examMinutes ? 'after' : 'before'} the start`) : '');
}

И ЛЕКО ТАРИКАТСКАТА:)

function onTimeForTheExam(input) {
    let examMinutes = parseInt(input[0]) * 60 + parseInt(input[1]);
    let studentMinutes = parseInt(input[2]) * 60 + parseInt(input[3]);
    let time = Math.abs(studentMinutes - examMinutes);

    console.log(studentMinutes > examMinutes ? "Late" : time <= 30 ? "On time" : "Early");
    console.log(time !== 0 ? (time < 60 ? `${time} minutes ${studentMinutes > examMinutes ? 'after' : 'before'} the start` :
        `${parseInt(time / 60)}:${time % 60 < 10 ? '0' : ''}${time % 60} hours ${studentMinutes > examMinutes ? 'after' : 'before'} the start`) : '');
}