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 tennis player swings his racket on a serve'. How many words start with the letter 'o' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'there is a man playing in a game of tennis'. How many words start with the letter 'i' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'gas station in sity with several cabs lined up'. How many words start with the letter 's' in the sentence.

Ex Output:

3