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: 'person in profile and sunlight at a barred window'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'car pass threw a green light in the day light'. How many words start with the letter 'd' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a flock of birds communicate with each other'. How many words start with the letter 'a' in the sentence.

Ex Output:

1