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

Ex Input:
Sentence: 'a man is holding a camera on a rig while skateboarding in a parking lot'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
4


Ex Input:
Sentence: 'a black horse standing on a hill top with a white horse'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3


Ex Input:
Sentence: 'a kid sitting on the ground with a stuffed bear'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:

2