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

Ex Input:
Sentence: 'a small boy standing on a platform next to a train'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3


Ex Input:
Sentence: 'a computer tore apart by a monitor keyboard and mouse on a desk'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3


Ex Input:
Sentence: 'a firetruck with a large yellow hose attached to a hydrant'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:

3