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: 'two elephants with people riding on them next to block barriers'. How many words start with the letter 'o' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a plate topped with steaks broccoli and carrots'. How many words start with the letter 'a' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a man riding a bike next to a yellow and blue train'. How many words start with the letter 'a' in the sentence.

Ex Output:

4