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 plate has ribs broccoli and mashed potatoes on a plate'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'two men are riding horses on a beach'. How many words start with the letter 'r' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a teddy bear wearing a red jacket sits on a beige carpet'. How many words start with the letter 'a' in the sentence.

Ex Output:

3