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: 'woman riding on the back of a horse inside a building'. How many words start with the letter 'o' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a zeppelin flying in the air as a water spouts occurs in a city lake'. How many words start with the letter 'a' in the sentence.

Ex Output:
5


Ex Input:
Sentence: 'a street sign is at a call city intersection'. How many words start with the letter 'i' in the sentence.

Ex Output:

2