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 refrigerator a white cabinet a microwave and some blue walls'. How many words start with the letter 'b' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'three black bears on or around a wooden play structure'. How many words start with the letter 's' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'japanese food of meat and vegetable are on a plate'. How many words start with the letter 'o' in the sentence.

Ex Output:

2