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

Ex Input:
Sentence: 'a man in a boat in a large lake'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3


Ex Input:
Sentence: 'a man sitting on a bench in a lobby'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3


Ex Input:
Sentence: 'a national express bus drives by other buses in a bus depot'. Count the occurrences of the word 'bus' in the given sentence.

Ex Output:

2