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 ladder sitting up against a red wall in a room'. How many words start with the letter 'a' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'man in winter clothes riding a snowboard on a gentle slope'. How many words start with the letter 'g' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a kite flying event in an open area on a sunny day'. How many words start with the letter 'o' in the sentence.

Ex Output:

2