import java.util.Scanner;
public class Frequency {


    public static void main(String[] args)

    {
    Scanner scan = new Scanner(System.in);

    int[] numbers;

    System.out.print("enter numbers: ");
     int [] distribution = new int[51];
Scanner scanner = new Scanner(System.in);
while (true)
{
        int num = scanner.nextInt();
        if (num <0 || num >50)
        {
                break;
        }
        distribution[num]++;
}

for (int i=0;i<51;i++)
{
        if (distribution[i]>0)
        {
                System.out.println(distribution[i]+" occurrences of " + i);
        }
}
    }
}