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

Ex Input:
Sentence: 'a crowd of people standing next to a bus'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
2


Ex Input:
Sentence: 'a large clock mounted to the side of a tall building'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
2


Ex Input:
Sentence: 'a man enjoys a continental breakfast and smiles a lot'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:

3