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

Input: Consider Input: Sentence: 'a man is surfing in a river while another person watches'. Count the occurrences of the word 'a' in the given sentence.

Output: 2


Input: Consider Input: Sentence: 'someone is holding up a hot dog with cheese on a bun'. Count the occurrences of the word 'a' in the given sentence.

Output: 2


Input: Consider Input: Sentence: 'group of fire fighters riding on the back of a fire truck'. Count the occurrences of the word 'back' in the given sentence.


Output: 1