In this task, you need to count the occurrences of the given word in the given sentence.

Ex Input:
Sentence: 'a man with a long grey beard in a white shirt and green tie at a pub full of greenshirted patrons'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
4


Ex Input:
Sentence: 'a chair in a corner next to a lampwith pictures behind it on a wall'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
4


Ex Input:
Sentence: 'a green tow truck parked next to a double decker bus'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:

2