The given sentence contains a typo which could be one of the following four types: (1) swapped letters of a word e.g. 'niec' is a typo of the word 'nice'. (2) missing letter in a word e.g. 'nic' is a typo of the word 'nice'. (3) extra letter in a word e.g. 'nicce' is a typo of the word 'nice'. (4) replaced letter in a word e.g 'nicr' is a typo of the word 'nice'. You need to identify the typo in the given sentence. To do this, answer with the word containing the typo.

Input: Consider Input: a re white yellow and black train coming down a track

Output: re


Input: Consider Input: Catas sleeping on top of a bed with blue and white striped blankets.

Output: Catas


Input: Consider Input: Two rtoothbrushes are in a holder with dental floss.


Output: rtoothbrushes