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

Ex Input:
Sentence: 'picture of a tab tub where the wall is open exposing wood studs and a shop vacuum is in the tub'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
2


Ex Input:
Sentence: 'a young man cutting a pizza on top of a table'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3


Ex Input:
Sentence: 'a man is lookng at his cell phone'. Count the occurrences of the word 'at' in the given sentence.

Ex Output:

1