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: 'japanese food of meat and vegetable are on a plate'. How many words start with the letter 'o' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a brown and white dog standing on a lush green field'. How many words start with the letter 'b' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a group of elephants walking around and grazing in a field'. How many words start with the letter 'a' in the sentence.

Ex Output:

4