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 in a body of water with a surf board'. How many words start with the letter 'b' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'woman standing on the beach with a large sailboat behind her'. How many words start with the letter 's' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a mother giraffe is nosing a young one to push it along'. How many words start with the letter 'i' in the sentence.

Ex Output:

2