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 large bathroom with double sinks and a walk in shower'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a man riding skis down the side of a snow covered ski slope'. How many words start with the letter 's' in the sentence.

Ex Output:
5


Ex Input:
Sentence: 'a woman swinging a tennis racquet on a tennis court'. How many words start with the letter 'a' in the sentence.

Ex Output:

3