#include <cstdio>
#include <iostream>
#include<stdlib.h>
using namespace std;


struct List
{
	int num;
	int st;
	List* next;
};
void add(List* l, int n, int s)
{
	List* q = l;
	List* w = new List();
	w->num = n;
	w->st = s;
	while(q->next != NULL)
		q = q->next;
	q->next = w;
	w->next = NULL;
}

int find(List* l, int a)
{
	List* w = l;
	while (w->num != a)
		w = w->next;
	if (w->st <= 3)
		return w->st;
	find(l, w->st);
}


void deletelist(List* l)
{
	List* q = l->next;
	while (q->next != NULL)
	{
		delete l;
		l = q;
		q = q->next;
	}
	delete q;
}

int main()
{
	FILE* f = fopen("7-1.txt","rt");
	int n = 0;
	fscanf(f, "%d", &n);
	List* l = new List();
	int a[100], m = 0, k = 0, fl = 0, i = 0;
	for (i = 0; i <= n; i++)
		a[i] = 0;
	i = 0;
	while (!(feof(f)) && i < n)
	{
		fscanf(f, "%d %d", &m, &k);
		if (k == 0)
		{
			if (fl == 0)
			{
				cout << "this students should be punished:" << '\n';
				fl = 1;
			}
			a[m] = 1;
			cout << m << '\n';
		}
		else
		{
			add(l, m, k);
			a[m] = 1;
		}
		i++;
	}
	if (i < n - 1)
	{
		if (fl == 0)
			cout << "this students should be punished:" << '\n';
		for (int j = 1 ; j <= n; j++)
			if (a[j] == 0)
				cout << j << '\n';
	}
	List* w = l;
	while (w->next != NULL)
	{
		if (w->st > 3)
			w->st = find(l, w->st);
		w = w->next;
	}
	if (w->st > 3)
			w->st = find(l, w->st);
	if (l->next != NULL)
		cout << "others:" << '\n';
	w = l;
	while(w->next != NULL)
	{
		w = w->next;
		if (w->num > 3)
			cout << w->num << " copied from " << w->st << '\n';
	}
	deletelist(l);
	return 0;
}