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.

Ex Input:
A coulpe of buses driving down a street next to tall buildings.

Ex Output:
coulpe


Ex Input:
A flqat screen television mounted above a fireplace.

Ex Output:
flqat


Ex Input:
A tifer cat sitting on top of a white purse.

Ex Output:

tifer