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: 'woman sitting at top of stairs talking on phone and smoking a cigarette'. How many words start with the letter 's' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a mother bear and her two young are crossing a shallow river'. How many words start with the letter 'a' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'a young man performing a skate board trick outside'. How many words start with the letter 't' in the sentence.

Ex Output:

1