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 [] attribute = new int[51];
    Scanner boomerang = new Scanner(System.in);

	while (true){
	int num = boomerang.nextInt();
	if (num <0 || num >50)
	{break;}
	attribute[num]++;}

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