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: 'several people watch cars drive by with bikes on them'. How many words start with the letter 'b' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a computer with a farm on the screen on top of a desk'. How many words start with the letter 'o' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'large clock tower lit up at night with an american flag at the top'. How many words start with the letter 'l' in the sentence.

Ex Output:

2