function examPreparation(input) {
    let gradesNumber = Number(input[0])
    let numberOfGrades = 0 //брой добри оценки
    let unsatisfactoryRating = 0 // брой незадоволителни оценки
    let sumGrades = 0 // сума оценки
    let taskCounter = 0

    let index = 1
    let nameTask = input[index]


    while (nameTask !== "Enough") {

        taskCounter++
        index++
        nameTask = input[index]

        let task = Number(input[index])
        if (task <= 4) {
            unsatisfactoryRating++
            sumGrades+=task

        } else {
            numberOfGrades++
            sumGrades += task
        }
        if (unsatisfactoryRating === gradesNumber) {
            console.log(`You need a break, ${unsatisfactoryRating} poor grades.`)
            break;
        } else {

            index++
            nameTask = input[index]

        }

    }
    let averageGrade = (sumGrades / taskCounter).toFixed(2)
    if (nameTask === "Enough") {
        console.log(`Average score: ${averageGrade}`)
        console.log(`Number of problems: ${taskCounter}`)
        console.log(`Last problem: ${input[index-2]}`)

    }


}