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: 'this is a dish of buttered asparagus with dressing'. How many words start with the letter 'o' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a group of kites flying before a big blue sky'. How many words start with the letter 'b' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a red and black train arriving at train station with people standing around'. How many words start with the letter 't' in the sentence.

Ex Output:

2