In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

Ex Input:
Sentence: 'a person riding their mountain bike off road'. How many words start with the letter 'r' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'white parrot sitting on a ledge eating a seed pod'. How many words start with the letter 'e' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a couple of giraffe standing on top of a grass covered field'. How many words start with the letter 'c' in the sentence.

Ex Output:

2