Problem #PRU-116539

Problemas Métodos Métodos algebraicos Particiones en pares y grupos; biyecciones Principio de la casa de palomas Principio de la casa de palomas (otros)

Problem

There are a thousand tickets with numbers 000, 001, ..., 999 and a hundred boxes with the numbers 00, 01, ..., 99. A ticket is allowed to be dropped into a box if the number of the box can be obtained from the ticket number by erasing one of the digits. Is it possible to arrange all of the tickets into 50 boxes?